What arguments from scripture are given by Baptists for the belief that one third of the angels were banished from heaven with Satan?

This is a long answer. Please bear with me.

I’m not sure how old this idea is, but its a combination of mistakes in interpretation. We always come into difficulties when we take any document out of context. The same is especially true for the Bible. That is what happens here and when done in several different bible passages, it leads to some man-made idea which is not taught in the bible.

Here are the passages which are used to explain this process. Notice how some can be taken out of context when a person just refers to a single verse or two.

Isaiah 14:12 “How you have fallen from heaven, O star of the morning, son of the dawn! You have been cut down to the earth, You who have weakened the nations!”

Luke 10:18 (the “He” is Jesus) And He said to them, “I was watching Satan fall from heaven like lightning.

II Peter 2:4-10 For if God did not spare angels when they sinned, but cast them into hell and committed them to pits of darkness, reserved for judgment; and did not spare the ancient world, but preserved Noah, a preacher of righteousness, with seven others, when He brought a flood upon the world of the ungodly; and if He condemned the cities of Sodom and Gomorrah to destruction by reducing them to ashes, having made them an example to those who would live ungodly lives thereafter; and if He rescued righteous Lot, oppressed by the sensual conduct of unprincipled men  (for by what he saw and heard that righteous man, while living among them, felt his righteous soul tormented day after day by their lawless deeds), then the Lord knows how to rescue the godly from temptation, and to keep the unrighteous under punishment for the day of judgment, and especially those who indulge the flesh in its corrupt desires and despise authority.

Jude 1:6-7 And angels who did not keep their own domain, but abandoned their proper abode, He has kept in eternal bonds under darkness for the judgment of the great day, just as Sodom and Gomorrah and the cities around them, since they in the same way as these indulged in gross immorality and went after strange flesh, are exhibited as an example in undergoing the punishment of eternal fire.

Revelation 9:1 Then the fifth angel sounded, and I saw a star from heaven which had fallen to the earth; and the key of the [a]bottomless pit was given to him.

Revelation 12:4 And his tail *swept away a third of the stars of heaven and threw them to the earth. And the dragon stood before the woman who was about to give birth, so that when she gave birth he might devour her child.

Let me break each passage down one by one.

First, Isaiah 14:12. Look at the context in Isaiah 14. The Lord God is speaking of rescuing His people from captivity. He will also punish their oppressors. Within this subject, God gives a “taunt” against the king of Babylon. Babylon was the ones who had taken God’s people captive. Daniel, Ezekiel, etc. were among those captives. Within the context of that “taunt” from God, it says the above passage. Taken within the context its about the king of Babylon. He had made himself out to be like God. Look at Daniel 7 and we can see this of Belshazzar in Daniel 5. He taunted God by drinking wine from the sacred vessels taken from God’s temple in Jerusalem and praised his gods. (see verse 22 - that is Daniel’s explanation.) This passage is not about the devil.

Luke 10:18 - Just before Jesus made this remark, seventy of His followers who had been sent out by Jesus returned happy because the demons had been subject to Jesus’ name. Jesus said “I was watching Satan fall from heaven like lightning.” Its not clear when Jesus saw this. But it connects with what the disciples were doing. The demons are being defeated by the name of Jesus. So we can safely say Satan fell from heaven.

II Peter 2:4-10 - All these events seem to be in order. The first one is when the angels sinned and they were “cast” into “hell”, also “committed” to “pits of darkness”. This sounds very much like Jude 1:6-7 where we learn they did not “keep their own domain”. They tried to usurp their authority. Now they are in hell.

Revelation 9:1 - Now we go to Revelation, which is highly symbolic since it is a series of visions. A “star from heaven” had “fallen” to the earth. It seems this “star” was given the key to the “bottomless pit”. He opened the bottomless pit and smoke and locusts came out of the pit. They had power to hurt only those people who did not have the “seal of God on their foreheads.” (v. 4) They could not kill anyone. Their power lasted five months. They also had a king over them (v.11), the “angel of the abyss”. His name is given. In Hebrew it is “Abaddon” and in Greek it is “Apollyon”. (v.11) It means “the destroying one” in both languages according to Strong’s accordance (see word # 623). This may have been part of God’s plan or even desire because this is the fifth trumpet. And notice this angel’s subjects are hurting only those who have not followed God. This is part of God’s judgment. Would Satan help God in His judgment?

Therefore, this “angel” had power or control over releasing these locusts, whatever they are or were. So far it says nothing about other angels or the devil. However, I’m sure many people think the “destroying one” fits the devil. But that doesn’t mean it is the devil.

Last, Revelation 12:4 - we read of a dragon. His tail “swept away a third of the stars of heaven and threw them to the earth”. This is the only passage that I am aware of in the bible that refers to a “third” of anything refering to something from heaven. But continue on. There is a woman in heaven. The dragon and the woman are both in heaven. This dragon stands before the woman who was about to give birth in order to devour her child. She gave birth to a male child who is to rule all the nations with a rod of iron. This sounds like Jesus. The description of a rod is used of him in Revelation and even in Genesis 41. But God rescued the child to His throne. The woman fled into the wilderness where she was nourished for a time. Then Michael and his angels waged war against the dragon and his angels (v. 7-8). The dragon was defeated and he was thrown down along with the angels (v. 9). So the dragon doesn’t quit. He goes after the woman. But she was given wings to rescue her so she could fly to the wilderness. In verse 9 the dragon is identified as the “serpent of old” (probably the Garden serpent) and as “Satan”. Now, notice also that his angels were thrown down with him to the earth. If the stars of heaven refers to angels, and the dragon threw them down with his tail, then why were they thrown down again later? That means they were back in heaven again. Did they come back? Why would the dragon cast them down in the first place with his tail? It seems God wants him and the angels who help him to be cast down. So why would Satan do purposefully what God wanted? And then change his mind and bring them back with him. And why would God let him? Therefore, it seems that it is saying Satan disrupted heaven. He did not belong there. That is what is meant by the sweeping away of the third of the stars. He was and is a trouble maker.

So these are the things I can be certain about from these passages:

Angels sinned against God because they did not remain in their proper domain or territory. When they sinned, the angels were cast into hell, a pit of darkness. Satan fell from heaven. Its already happened. An angel was given charge or control over the bottomless pit. He opened it up and locusts came out. They could only hurt people who have rejected God. Therefore, this is a judgment from God. The dragon in Rev. 12 is Satan. Satan tried to eat Jesus but God took Him to His throne. The stars the dragon swept away with his tail were not angels. Satan had angels to help him in a fight against Michael. He lost that fight and he and his angels were cast down to the earth. From there he persecuted the woman. But God rescued her. Satan goes off to make war against the rest of the woman’s descendants. God is in control.

As you have rightly said the number one third comes from the Revelation. And that alone is solid Biblical support, since this was referring to a past event, and not prophesy.

There is an erroneous, but widely accepted belief that the Revelation is all prophesy, but this verse tells us that this is not true:

Revelation 1:19 KJV Write the things which thou hast seen, and the things which are, and the things which shall be hereafter;

The things thou hast seen is not restrictive to those enumerated in the Revelation. There was no reason to teach him what he already knew and so the Revelation is dedicated to the things that are and are to come until chapter 12, where he tells of the things of the past which is basically a historical record beginning before creation, and the expulsion of the Devil and up through the history of the Nation of Israel. It is not sequential, it is based on the execution of God's plan.

The study of the Revelation and it's meanings is extremely interesting, and the above is taken from several well known Bible commentaries. Although the words are mine the synopsis is a conglomeration of the opinions of more than five commentators. I will be happy to give a list of these if you desire, but will not do so here as lists are not a good answer for this site.