Does God need food and water to stay alive?

Whatever the intention behind the question is, in my experience it is usually posed by Muslims. This question demonstrates the appalling lack of proper understanding of Christian faith about Jesus Christ, His deity and humanity, as far as the Biblical teachings are concerned. Here I attempt to answer each sub question separately...

Does God need food and water to stay alive?

No! As a matter of fact, the question is an invalid question. Because by definition God is the necessary and self-existent Being, and He is not a biological being that needs food and water. Furthermore, God doesn't depend on anything for His 'life,' rather it is He on whom everything else depends. Hence the question is invalid and thus nonsensical!

Did Jesus Christ need food and water to stay alive?

Yes! When Jesus Christ lived on this earth as a human being, yes He needed food and water to stay alive like any other human being. Perhaps this is the only valid and meaningful question out of three questions posed by the questioner.

Was Jesus Christ the God when he needed food and water to stay alive?

Again, this is also not a valid/meaningful question. If one wants to know who Jesus Christ was when He was on this earth one would do well to pay attention to the teaching of God's true word the Bible in this matter. As per the Bible, Jesus existed in the form of God or God's Word prior to His birth as a human being in this world [John.1:1-14; Philippians 2:5-8].

However, Jesus took on human form and nature and entered into this world [Hebrews.10:5]. In other words, although He was in the form of God and was God He voluntarily put aside His divine prerogatives and restricted Himself to human limitations. Jesus did not come into this world as God, but man! Thus He was a perfect human being while His divinity was hidden behind his human body and nature.

During His life on this earth, Jesus Christ was God in human form and nature. He had both divine and human natures, yet they were not intermingled. Which is why He needed food, water, and oxygen to be alive i.e. biologically, just like any other human being. But as God he did not need any of them. The interface between the Creator and creation in Jesus Christ is a mystery belongs to God [Col.2:2], which is possible only for True God!

God is complete in Himself,the self existent one,the I am,the alpha and Omega. God owns the world,He made it for His pleasure. My God is awesome, glorious in all His ways.

In short God is the progenitor of all things, nothing exists outside of Him therefore He is all sufficient and in need of nothing. Especially not food or water.

The question ought to be qualified because Jesus the second person in the echâd Godhead has existed as God in four different forms.

And whilst incarnate because of the limitations of the body given Him, He got hungry.

“And after fasting forty days and forty nights, he was hungry.” ‭‭Matthew‬ ‭4:2‬ ‭

But generally people think of God the Father or the Holy Spirit in spirit form. Bible says

“God is spirit, and those who worship him must worship in spirit and truth."” ‭‭John‬ ‭4:24‬ ‭

Jesus makes a distinction between a spirit and a body (whether mortal or glorified)

“See my hands and my feet, that it is I myself. Touch me, and see. For a spirit does not have flesh and bones as you see that I have."” ‭‭Luke‬ ‭24:39‬ ‭

The Bible also says this about the Kingdom

“For the kingdom of God is not a matter of eating and drinking but of righteousness and peace and joy in the Holy Spirit.” ‭‭Romans‬ ‭14:17‬ ‭

Sustenance is not therefore necessary though heaven does contain food and water

“Yet he commanded the skies above and opened the doors of heaven, and he rained down on them manna to eat and gave them the grain of heaven. Man ate of the bread of the angels; he sent them food in abundance.” ‭‭Psalms‬ ‭78:23-25‬ ‭

And

“Then the angel showed me the river of the water of life, bright as crystal, flowing from the throne of God and of the Lamb” ‭‭Revelation‬ ‭22:1‬ ‭

Not forgetting the marriage supper of the Lamb which is a feast and banquet

But does God need food and water? No, quite simply if He did then He would not be all sufficient and yet Scripture says that He is and that all things derive their existence from Him, by Him and for Him.

“For from him and through him and to him are all things. To him be glory forever. Amen.” ‭‭Romans‬ ‭11:36‬ ‭

God being life doesn’t need anything to gain or maintain life. Food and drink need God to exist but God doesn’t need food and drink.

It's an odd question.

Surely you know that God needs nothing.

He lived for an eternity before he made the Universe. For an eternity, before God made the Universe, with its food and water, there was literally nothing except God.

He didn't need anything then, and he doesn't need anything now outside of himself.

Perhaps you are wondering if Christianity is even slightly in agreement with common knowledge and common sense?

The Bible makes clear God made all things out of nothing:

"In the beginning God created the heavens and the earth." Genesis 1:1

So said the Apostle Paul in the New Testament of the Bible:-

"Then Paul stood in the middle of Mars' hill, and said, Men of Athens, I perceive that you are very religious in every way. For while I was passing through and examining the objects of your worship, I also found an alter with this inscription, "TO THE UNKNOWN GOD". Whom therefore you worship in ignorance, him declare I unto you.

God that made the world and all things in it, seeing that he is Lord of heaven and earth, dwells not in temples made with hands; nor is he served by human hands, as though he needed anything, since he himself gives to all life and breath and all things; (Acts 17:25)

and he made from one man every nation of mankind to live on all the face of the earth, having determined their appointed times and the boundaries of their habitation, that they would seek after God, if perhaps they might grope for him and find him, though he is not far from each one of us;

for in him we live and move and are; as even some of your own poets have said "For we also are his children".

Being then the children of God, we ought not to think that the Divine Nature is like gold or silver or stone, an image formed by the art and thought of man.

The times of this ignorance God has overlooked: but now he commands all men every where to repent because he has appointed a day, in the which he will judge the world in righteousness by the man he has ordained, and he has given assurance to all men, in that he has raised him from the dead. (Acts 17:22-31)

No. God exists necessarily, it is his essence to exist. Therefore, He can not not to exist.

We see this from scripture also, Exodus 3:14:

God said to Moses, “I AM WHO I AM. This is what you are to say to the Israelites: ‘I AM has sent me to you.

From this follows that God does not need anything that is extrinsic to Him to sustain Him.

Also note that God is not material, but pure spirit. This is confirmed by the scripture in John 4:24:

God is Spirit, and His worshipers must worship Him in spirit and in truth.

Edit. About Jesus specifically and does his human nature require him to eat and drink the answer is no. You can find an explanation in Aquinas's Summa Theologiae here.