How did the early Christians and Apostles Get into the temple? Shouldn't they have been stoned by the Jews for preaching Jesus as God?

It is possible because in that period (the 2nd temple period), believing Jesus was God wasn't a strange thing, as many Jews at that time believed in a second Yhwh as evident in a plethora of ancient Jewish texts. Philo of Alexandria, also a monotheistic Jew in the first century, believed in a "second God" (deuteros theos). Scholars formally called this as the "Second Power" which only deemed heretical by the Jews in the late second century A.D.

"The binitarian portrayal of Yahweh in the Hebrew Bible was motivated by this belief. The ancient Israelite knew two Yahwehs—one invisible, a spirit, the other visible, often in human form. The two Yahwehs at times appear together in the text, at times being distinguished, at other times not. Early Judaism understood this portrayal and its rationale. There was no sense of a violation of monotheism since either figure was indeed Yahweh. There was no second distinct god running the affairs of the cosmos. During the Second Temple period, Jewish theologians and writers speculated on an identity for the second Yahweh" (UW-Madison, 2004).

Bible scholars say that Jesus was worshiped as God quite rapidly (within months after Jesus' ascension).

To underscore the chronological point here, this body of beliefs and practices clearly emerged and became familiar features of circles of believers within the scarcely two decades between Jesus’ crucifixion and the earliest of Paul’s letters.

Indeed, we should probably judge that this remarkable development emerged within the very earliest years, perhaps more accurately within the earliest months, after Jesus’ death, ca. 30 A.D. (The Origins of Devotion to Jesus in its Ancient Context, Larry Hurtado).

Plus, the emerging consensus among scholars today was that Jesus was not a mere man, but had preexistence as God, which was known in scholarly term as ''early high christology''.

The recent work of Larry hurtado and Richard Baukham on the shape and origins of early Christology has led to an emerging consensus. Few would now doubt that a 'high' Christology is present in the earliest text of the New Testament (Crispin Fletcher-Louis, 2015).

"The experiences of the risen Jesus were crucial; a “high” view of Jesus erupted early (i.e., a view of Jesus as worthy of divine honors and reverence); the notion of “pre-existence” likewise was early. I don’t find plausible his claim that Paul saw Jesus as an angel, or that the view of Jesus as installed as God’s “Son” and the “Lord” at his resurrection and the view that Jesus was “pre-existent” were two separate strands of thought. The latter seems to me to have emerged quite readily from the former". (Larry Hurtado, Oct. 2016).

"I have been trying to explain the unusually important statement about Christ in Paul’s “Christ Poem” in Phil. 2:6-10. It’s an extremely high Christology. Christ is a divine being before coming into the world; and at his exaltation he was made equal with God" (Bart Ehrman, Paul’s Incredibly High Christology, 2020).

Monotheism in early Judaism and Christianity is inclusive and it isn't unitarian so that is why there was no controversy when Christians preached and worshiped Jesus as God in the Jewish Temple.

OP is clearly looking at the first Christians (who were not called that yet) through a modern orthodox perspective, instead of an early to mid 1st century perspective. It took a half century or more for Jesus to be elevated to Godhood in Christian doctrine. A close reading of the NT, especially the Gospels, shows hints that Jesus wasn't considered the SOn of God until after the Resurrection. Then eventually, it was moved to His baptism. ("This day have I begotten You.") Still later, this original adoptionism was moved further back to His birth. Finally, He was considered as divine and always the Son without adoption with a pre-incarnate existence. However, it wasn't the Jerusalem apostolic leadership developing this doctrine, but the evolving Pauline and signs and wonders sects. James, Peter, etc. probably didn't consider and preach Jesus as God -- Messiah, yes, but a Jewish model of the Messiah, which requires no Godhood of the Messiah. Remember, Jesus was killed for royal pretensions, as a Messianic figure would be. Look at the charge that was hung on the cross. "King of the Jews" The Jews believed Messiah to be a man of the line of David, not God, to hold the throne of David according to the will of God, in fulfillment of His promise to David and repeated in the prophets. Consider this, out of the many, many Jewish Messiah figures, none other than Jesus has ever been considered anything but human.

Before concluding with the answer, it's important to clear up a misconception in the question - that Jesus is God was taught in the temple by the apostles. (certainly this particular verse does not suggest this)

Does Jesus being the son of God make him God?

Being called the son of God was made clear from his conception and birth.

Luke 1:35 And the angel answered her, “The Holy Spirit will come upon you, and the power of the Most High will overshadow you; therefore, the child to be born will be called holy—the Son of God.

Confirmed by Jesus’ disciples

Matthew 16:16 Simon Peter replied, “You are the Christ, the Son of the living God.” John 20:31 But these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name. Mark 1:1 The beginning of the gospel of Jesus Christ, the Son of God.

The demons.

Mark 3:11 And whenever the unclean spirits saw him, they fell down before him and cried out, “You are the Son of God.” Luke 4:41 And demons also came out of many, crying, “You are the Son of God!”

Made clear by the Father.

Matthew 3:17 And behold, a voice from heaven said, “This is my beloved Son, with whom I am well pleased.”

And by Jesus’ own words.

John 17:1 When Jesus had spoken these words, he lifted up his eyes to heaven, and said, “Father, the hour has come; glorify your Son that the Son may glorify you. John 11:4 But when Jesus heard it he said, “This illness does not lead to death. It is for the glory of God, so that the Son of God may be glorified through it.”

There are many references to other sons of God who are not sinless and holy as Jesus was, they are also men as Jesus certainly was. So, having the title, ‘son of God’, does not make one God.

Matthew 5:9 “Blessed are the peacemakers, for they shall be called sons of God. Romans 8:14 For all who are led by the Spirit of God are sons of God. Luke 3:38 The son of Enos, the son of Seth, the son of Adam, the son of God.

Even angels – and they are not God either – even though many are without sin.

Job 38:7 When the morning stars sang together and all the sons of God shouted for joy? Job 1:6 Now there was a day when the sons of God came to present themselves before the LORD, and Satan came also among them.

SO, being a ‘son of God’ does not make one God. How else might we determine if Jesus is God or not? (as the Op has surmised)

There are many other clear passages providing food for thought and careful consideration. Jesus has a God – while on earth as a man, and while raised, ascended and exalted, as a man.

2 Cor 1:3 Blessed be the God and Father of our Lord Jesus Christ. Also 1 Pet 1:3 ad many others. Heb 1:9 You have loved righteousness and hated wickedness; therefore God, Your God, has anointed You (Jesus) above Your companions with the oil of joy. Acts 2:36 Therefore let all Israel know with certainty that God has made this Jesus, whom you crucified, both Lord and Christ!”

Rev 3:12 The one who overcomes, I (Jesus) will make him a pillar in the temple of my God, and he will not go out from it anymore; and I will write on him the name of my God, and the name of the city of my God, the new Jerusalem, which comes down out of heaven from my God, and my new name.

John 17:3 Now this is eternal life, that they may know You, the only true God, and Jesus Christ, whom You have sent. John 20:17 “Do not cling to Me,” Jesus said, “for I have not yet ascended to the Father. But go and tell My brothers, ‘I am ascending to My Father and your Father, to My God and your God.’ ” (don’t be misled by the textual additions of ‘returning’ or ‘going back’ in the passages that speak of Jesus going to the Father after his resurrection – there is no such concept in the Greek. Many translators have added the extra words to these verses, John 16:5,28, 13:1,3, 20:17, 14:28)

1 Tim 2:5 For there is one God, and there is one mediator between God and men, the man Christ Jesus. Heb 1:2 But in these last days He has spoken to us by His Son, whom He (God) appointed heir of all things. John 5:26 ‘The Father gave the son to have life in himself’. Gal 4:4 ‘God sent His son, born of a woman’. John 5:19, ‘the son can do nothing by himself…’, ‘my words are not my own but the Father’s’, John 14:24

Clearly we see a striking demarcation between God – the creator of all, and the son called Jesus who God made Lord, Christ, heir, who gave life (twice), all the words and works are not from Jesus, but from God through Jesus.

If we are to maintain the presumption that Jesus is God, we must ignore all the evidence to the contrary – of which I have provided a small sample.

We are also faced with the fact that Jesus never said he was God, nor his disciples or apostles nor any prophecy.

No, they would not have been stoned for teaching Jesus is God. No one was teaching such a thing as this concept was introduced decades after Jesus ministry, and then it was centuries after that before the final draft of a trinity which formally mandated that Jesus is God the Son – not by divine revelation, but by the power of political forces using their own authority for such matters to misdirect the early church. from the biblical, gospel message they began with.

As was very nicely described by Anne, the Spiritual power evident in the early church had an influence much greater than men on their own. The Jews were being converted from their OT model into the NT model based not on laws (of which there were many!) but on a new model of faith and grace, forgiveness and salvation – leading to a resurrection and eternal life.

It would have been an exciting time as some were converted and clearly others were not – perhaps dividing friends and family – all were part of the temple culture, which was now being dramatically transformed from within! It wouldn't be long before persecution set in and the church faithful were severely tested.

It must be recognised that genuine church growth did not happen because people decided to believe - but rather because God enabled a belief through His spirit in their lives. The same is true today. One cannot discover God unless God first makes Himself known - even in a manner that we are initially oblivious to. This was well expressed in Jesus discourse with Peter, 'flesh and blood did not reveal this to you...' Matt 16:17

OP: "Every day they continued to meet together in the temple courts. They broke bread in their homes and ate together with glad and sincere hearts, praising God and enjoying the favor of all the people. And the Lord added to their number daily those who were being saved."

OP: But how is it possible they could get into the temple every day?

It says they got into the temple courts. There were different courts for different groups like gentiles, women, or priests. See here for example.

OP: Wouldn't the Jews stone them to death for preaching Jesus as God? The Jews would have heavily outnumbered them, I don't understand how this could have happened.

Acts 6:7 also informs that a number of priests converted.

And the word of God increased; and the number of the disciples multiplied in Jerusalem greatly; and a great company of the priests were obedient to the faith.

But this is not to say that there wasn't attempts to stop them. For example, Acts 4:18

And they [high priests and elders] called them [Peter and John] in and ordered them not to speak or teach at all in the name of Jesus.

OP: Why did they "enjoy the favor of all the people?" Wouldn't the people hate them for declaring that a man is God? Or at a minimum, wouldn't at least the Pharisees hate them?

As shown in Acts, there was never a smooth, painless transition to explain that Jesus is the Christ prophesied in the OT and fulfilled before their very eyes.

Perhaps a better question might be why wouldn't everyone believe? Miracles, fulfilled prophecy. But for some, there might be a loss of privilege, power, pocketbook.

Acts 5:39 But if it is from God, you will not be able to stop these men; you will only find yourselves fighting against God.”

And then before Jesus died, there is this record.

John 11:45-53 Therefore many of the Jews who had come to visit Mary, and had seen what Jesus did, believed in him. But some of them went to the Pharisees and told them what Jesus had done. Then the chief priests and the Pharisees called a meeting of the Sanhedrin. “What are we accomplishing?” they asked. “Here is this man performing many signs. If we let him go on like this, everyone will believe in him, and then the Romans will come and take away both our temple and our nation.” Then one of them, named Caiaphas, who was high priest that year, spoke up, “You know nothing at all! You do not realize that it is better for you that one man die for the people than that the whole nation perish.” He did not say this on his own, but as high priest that year he prophesied that Jesus would die for the Jewish nation, and not only for that nation but also for the scattered children of God, to bring them together and make them one. So from that day on they plotted to take his life.

Thank you for adding that you are asking the question from an Islamic perspective. To quote your comment,

“The disciples proclaiming Jesus as the Messiah is correct in Islam. But to claim a man is God is utterly false from the Islamic point of view. It makes sense that the disciples could proclaim Jesus as the Messiah. But if they were claiming he was God, then they would be stoned to death. So my question is, how did the disciples go into the Jewish Temple and proclaim Jesus is God without being stoned to death immediately, not in 60 AD or so. Surely they only claimed he was the Messiah.”

You have raised a profoundly important point, worthy of a clear explanation from the point of view of the people involved, at that time. Those people were the Jews, the Christians and the Romans circa 30 A.D. Those people were aware of the life and times, and claims of Jesus of Nazareth, who had not long been crucified by the Roman authorities. Now, this immediately raises a problem with your question because the Islamic perspective is that Jesus of Nazareth did not die on a Roman cross. The teaching of the Qur’an is that Jesus never died; that he was taken up to heaven without ever dying, physically.

“They that said (in boast), ‘We killed Christ Jesus the son of Mary, the Messenger of Allah’ – but THEY KILLED HIM NOT, NOR CRUCIFIED HIM, but so it was made to appear to them, and those who differ therein are full of doubts, with no (certain) knowledge, but only conjecture to follow, for of a surety THEY KILLED HIM NOT – nay, Allah raised him up unto Himself.” (Surah 4:157-158 emphasis mine. I quote from the translation by Abdullah Yusuf Ali, of 2000 Wordsworth Editions Ltd.)

The people of that time were not Muslims, however. Those who witnessed the crucifixion of Jesus of Nazareth were Jews and Christians and Romans circa A.D. 30. To understand why Jews allowed Jewish Christians into their Temple in Jerusalem, despite all they were claiming about a resurrected Christ who they had witnessed with their own eyes ascending back to heaven (from where he had originated), we have to stick to the historic records of that time, not anything claimed some 600 years later. Such claims are an interpretation of historic events. But your question only asks for explanations from the people involved, and the record we have of that is in the biblical book of Acts, written circa A.D. 63 and based on eye-witness accounts.

The simple answer is that on the day of Pentecost following many Christians seeing their resurrected Jesus ascend bodily up into the sky, till clouds hid him from their view, some 3,000 Jews and proselytes were converted to faith in this risen Christ by the public witness of the Apostles (see Acts chapter 2). Jerusalem was awash with the power of the Holy Spirit at work. Then the record states:

“They devoted themselves to the apostles’ teaching and to the fellowship, to the breaking of bread and to prayer. Everyone was filled with awe, and many wonders and miraculous signs were done by the apostles. All the believes were together and had everything in common. Selling their possessions and goods, they gave to anyone as he had need. Every day they continued to meet together in the temple courts. They broke bread in their homes and ate together with glad and singleness of heart, praising God and enjoying the favour od all the people. And the Lord added to their number daily those who should be saved.” (Acts 2:42-47)

It was the work of God’s Holy Spirit that ensured they were not thrown out of the Temple, let alone stoned for blasphemy. The Temple authorities dare not meddle with a clear demonstration of the power of God’s Holy Spirit. They had tried to stone Jesus to death for claiming to be the I Am (who spoke to Moses at the burning bush, John chapter 8). But the Holy Spirit who protected Jesus then from being stoned to death, also protected the apostles and Christians glorifying God in the Temple, after Jesus’ resurrection.

But if you deny that Jesus was crucified (logically meaning that, to you, he could not have been resurrected) then you will never understand the thinking and actions of the people in Jerusalem’s Temple during that amazing time in history.

How did the early Christians and Apostles get into the temple? Shouldn't they have been stoned by the Jews for preaching Jesus as God?

The answer seems to be quite simple: One of the disciples was known to the chief priests!

Peter's First Denial

15Now Simon Peter and another disciple were following Jesus. Since that disciple was known to the high priest, he also went with Jesus into the courtyard of the high priest. 16But Peter stood outside at the door. Then the disciple who was known to the high priest went out and spoke to the doorkeeper, and brought Peter in. 17At this, the servant girl watching the door said to Peter, “Aren’t you also one of this man’s disciples?” “I am not,” he answered.…

Thus it seems possible that St. John brought in the true disciples of Jesus into the temple!

We must remember also that at this point in history, the Jews were under Roman occupation and were not allowed to inflict the death penalty in Palestine.

However St. Paul was physically chastised for preaching the Gospel of Jesus Christ, including one stoning and three whippings.

Paul's Suffering and Service

…24Five times I received from the Jews the forty lashes minus one. 25Three times I was beaten with rods, once I was stoned, three times I was shipwrecked. I spent a night and a day in the open sea. 26In my frequent journeys, I have been in danger from rivers and from bandits, in danger from my countrymen and from the Gentiles, in danger in the city and in the country, in danger on the sea and among false brothers,… - 2 Corinthians 11:25

Simply reading through the four gospel accounts and Acts gives a very clear picture indeed of a time of transition, a time of further revelation, a time of in-gathering, a time of fulfilled prophecy, a time of re-structuring . . . .

. . . and a time of opposition, a time of conflict, a time of violent suppression, and a time of martyrdom . . .

. . and the gradual forming of a separate body called The Church (which had no requirement, whatsoever, for a 'temple made with hands').

Howbeit the most High dwelleth not in temples made with hands; as saith the prophet, [Acts 7:48 KJV]

Thus saith the LORD, The heaven is my throne, and the earth is my footstool: where is the house that ye build unto me? and where is the place of my rest? For all those things hath mine hand made, and all those things have been, saith the LORD: but to this man will I look, even to him that is poor and of a contrite spirit, and trembleth at my word.

Isaiah 66:1,2 KJV]

Christians who were Jews got into the temple by walking through the gates. Jewish men (who were circumcised), Jewish women and even Gentiles had their own areas within the temple where they were welcome.

The Bible has different accounts of how Jesus and those who followed him were allowed free access into the temple. Jesus, his family members and others, would come to the temple for the annual feasts and festivals.

Of course, the temple was destroyed in 70 A.D. and that brought an abrupt end to all temple worship.

As for the events described in Acts chapter 2 after the Holy Spirit came at Pentecost and God added to the numbers of the church daily, they enjoyed fellowship, one with another, and also met together in the temple courts.

They broke bread in their homes and ate together with glad and sincere hearts, praising God and enjoying the favour of all the people. And the Lord added to their number daily those who were being saved (Acts 2:46-47).

As a matter of interest, it has been suggested that there were about 100,000 Christians around that time when Christianity exploded onto the world. Amazing what God can do!

Edit in response to the additional information you have provided, looking at this from the view of Islam:

Although Muslims see Jesus as being one of the most important prophets, Islam asserts that Jesus, though born of a virgin, was created like Adam. Muslims do not believe Jesus died on the cross or that he was resurrected. Most important is the Islamic belief that there is only one God, only one Allah, and that it is blasphemy to think Jesus was either the Son of God or part of the one being of God. The difficulty with your question is that the first Christians did not go into the temple declaring "Jesus is God!"

I suggest you need to ask a different question, because the issue here is the Christian belief in the eternal existence of the Word, or Logos, of God who was with God in the beginning and who is God. Jesus of Nazareth was no ordinary mortal, nor was he just a prophet. Your question is unanswerable from a Christian perspective because it does not focus on who Jesus REALLY is.

In the temple the apostles preached about the resurrected Jesus and they healed in the name of Jesus. The chief priests “commanded them not to speak or teach at all in the name of Jesus” (Acts 4:18). “Day after day, in the temple courts and from house to house, they never stopped teaching and proclaiming the good news that Jesus is the Christ” (Acts 5:42). That is why the Jewish religious leaders hated them, because they spoke of Jesus as being resurrected by God, of Jesus being seated at the right hand of God, and of Jesus being the Christ, the Messiah.

Paul said (in a synagogue in Damascus) that Jesus is the Son of God (Acts 9:20) and the proof of his deity was his resurrection from the dead (Romans 1:1-6). The Jewish religious leaders knew that to claim to be the Son of God was blasphemy, and that is the very reason they plotted to have Jesus killed because Jesus acknowledged he was the Son of God (Matthew 26:63-64). But the apostles never said “Jesus is God” and that is why they were not stoned.

In Acts chapters 3 and 4 we have a record of Peter's early preaching within the temple courts after a lame beggar was healed in Jesus' name:

And when Peter saw it he addressed the people: “Men of Israel, why do you wonder at this, or why do you stare at us, as though by our own power or piety we have made him walk? The God of Abraham, the God of Isaac, and the God of Jacob, the God of our fathers, glorified his servant Jesus, whom you delivered over and denied in the presence of Pilate, when he had decided to release him. But you denied the Holy and Righteous One, and asked for a murderer to be granted to you, and you killed the Author of life, whom God raised from the dead. To this we are witnesses. - Acts 3:12-15

And as they were speaking to the people, the priests and the captain of the temple and the Sadducees came upon them, greatly annoyed because they were teaching the people and proclaiming in Jesus the resurrection from the dead. And they arrested them and put them in custody until the next day, for it was already evening. But many of those who had heard the word believed, and the number of the men came to about five thousand. - Acts 4:1-4

Not long after Peter was again preaching in the temple courts and was arrested by the High Priest and the Sadducees (the ruling council in the temple who did not believe in the resurrection from the dead):

And when they had brought them, they set them before the council. And the high priest questioned them, saying, “We strictly charged you not to teach in this name, yet here you have filled Jerusalem with your teaching, and you intend to bring this man's blood upon us.” But Peter and the apostles answered, “We must obey God rather than men. The God of our fathers raised Jesus, whom you killed by hanging him on a tree. God exalted him at his right hand as Leader and Savior, to give repentance to Israel and forgiveness of sins. And we are witnesses to these things, and so is the Holy Spirit, whom God has given to those who obey him.” When they heard this, they were enraged and wanted to kill them. - Acts 5:27-33

The next section of Acts demonstrates how there was division and differences even amongst members of the ruling council and begins to explain how their presence and teaching in the temple could both be abhorred and yet also tolerated:

But a Pharisee in the council named Gamaliel, a teacher of the law held in honor by all the people, stood up and gave orders to put the men outside for a little while.  And he said to them, “Men of Israel, take care what you are about to do with these men. For before these days Theudas rose up, claiming to be somebody, and a number of men, about four hundred, joined him. He was killed, and all who followed him were dispersed and came to nothing. After him Judas the Galilean rose up in the days of the census and drew away some of the people after him. He too perished, and all who followed him were scattered. So in the present case I tell you, keep away from these men and let them alone, for if this plan or this undertaking is of man, it will fail;  but if it is of God, you will not be able to overthrow them. You might even be found opposing God!” - Acts 5:34-39

We do not have a record of the Apostles declaring "Jesus is God!" in the temple. He was preached as the Christ that the prophets had foretold, he was preached as the Son of God, he was preached as the resurrection from the dead, and he was preached as the only Name under heaven by which we must be saved. The giving of the Holy Spirit at Acts chapter 2 represents the starting point of the deepening of the understanding of those terms in the hearts of believers.

John's Gospel contains much of the foundational material under-girding the trinitarian understanding of Jesus as God the Son. A likely dating for the writing of John's gospel, in which Jesus is proclaimed as the incarnation of that Word that was God (John 1:1), is after the destruction of the temple. It could be that Jesus as God the Son was not yet a formalized teaching in the very early days. It could also be that the terms Messiah and Christ were always meant to contain those concepts. What was definitively being preached by Christians in the temple was repentance from sins, eternal life, and resurrection in Jesus' name.

1. Insufficient Authority

This answer sheds light on the question: https://hermeneutics.stackexchange.com/questions/5558/in-the-time-of-jesus-were-the-jewish-authorities-allowed-to-execute

The Jews were not permitted to sentence a person to death without the consent of the governing Roman official. The above article (citing Josephus) shows how, after one official (Porcius Festus) died in office, before his replacement could be sent from Rome, the high priest arrogated the power to have James, a leader in the Christian church, executed. Once the new Roman official arrived, he removed that high priest from office for this serious breach.

2. Fear of the Crowd

25 Then someone came and said, “Look! The men you put in jail are standing in the temple courts teaching the people.” 26 At that, the captain went with his officers and brought the apostles. They did not use force, because they feared that the people would stone them. (Acts 5:25-26)

3. Fear of Public Opinion, possible insurrection

Peter healed a lame man in the temple courts in front of a crowd. This made him popular.

13 When they saw the courage of Peter and John and realized that they were unschooled, ordinary men, they were astonished and they took note that these men had been with Jesus. 14 But since they could see the man who had been healed standing there with them, there was nothing they could say. 15 So they ordered them to withdraw from the Sanhedrin and then conferred together. 16 “What are we going to do with these men?” they asked. “Everyone living in Jerusalem knows they have performed a notable sign, and we cannot deny it. 17 But to stop this thing from spreading any further among the people, we must warn them to speak no longer to anyone in this name.” (Acts 4:13-17)

4. Futility of Legal Measures and God's Protection

When the authorities did arrest the Apostles, on occasion God would send angels to set them free.

17 Then the high priest and all his associates, who were members of the party of the Sadducees, were filled with jealousy. 18 They arrested the apostles and put them in the public jail. 19 But during the night an angel of the Lord opened the doors of the jail and brought them out. 20 “Go, stand in the temple courts,” he said, “and tell the people all about this new life.”

If God's holy angels told the Apostles to stand in the temple courts, they were well protected.