If God and Jesus are the same, having the same mind, knowledge and power, then why would Jesus beg himself in the garden of Gethsemane, to spare himself from having to be crucified? Furthermore, why would Jesus ask himself why he has forsaken himself by allowing himself to be crucified?
Jesus is equally God while still not God the father as well as not being God the Holy Spirit. They are three separate entities that all form the single God-head. John's gospels shows this to us.
"In the beginning was the Word, and the Word was with God, and the Word was God. 2 He was in the beginning with God. 3 All things were made through Him, and without Him nothing was made that was made. 4 In Him was life, and the life was the light of men. 5 And the light shines in the darkness, and the darkness did not comprehend it. 6 There was a man sent from God, whose name was John. 7 This man came for a witness, to bear witness of the Light, that all through him might believe. 8 He was not that Light, but was sent to bear witness of that Light. 9 That was the true Light which gives light to every man coming into the world.10 He was in the world, and the world was made through Him, and the world did not know Him. 11 He came to His own, and His own did not receive Him. 12 But as many as received Him, to them He gave the right to become children of God, to those who believe in His name: 13 who were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God. 14 And the Word became flesh and dwelt among us, and we beheld His glory, the glory as of the only begotten of the Father, full of grace and truth." - John 1:1-14
So once we understand that Jesus was not merely talking to Himself in Gethsemane nor upon the Cross. The question becomes. How could Jesus, being part of the God head, ask to be spared from that which he knew he must do?
Answer. Because while being 100% God he was also 100% man while in the flesh. The bible says that he felt every temptation, knew every pain that man feels. Nothing was withheld from him. So then once we understand that we can ask ourselves what person wouldn't beg to spared of such a painful way to die. Then we are also shown a beautiful example of obedience in that Christ said, "Not my will, but yours." Even knowing what awaited him he obeyed God.
Now to the second part of the question Why would he ask why he was forsaken? Because for the first and only time in eternity. Christ was separated from God's presence. All the sins of all mankind were placed upon Jesus. God is so Holy that he -can not- be in the presence of sin. He can't. It's not an option. Even for the love of his only begotten. Therefore Jesus was indeed forsaken in that instance. Alternatively, Jesus was fulfilling a prophetic scripture in his crying out as well.
"My God, My God, why have You forsaken Me?.." -Psalm 22:1
I hope this helps. God bless
The question is based on a misunderstanding of the Trinity. While Jesus and the Father are both God, Jesus is not the same as the Father. God is "three persons in one God", those three persons being the Father, Son and Holy Spirit.
You might like to read the Athanasian Creed, which is a definitive (but not simple) statement of the Trinity.
The doctrine of the Trinity is nowhere to be found in the bible. The only 2 passages that mention the trinity (Matthew 28:19 and 1 John 5:7,8) are considered to be forgeries. The form that they are in the KJV is not consistent with the oldest and most reliable manuscripts that we have.
Simply put, Jesus is not God nor was he ever. The doctrine of the Trinity is a false doctrine that was in development in the Orthodox church during the second and third centuries and was fully developed by the end of the fourth century when the holy ghost was added to make it a full trio.
Jesus, being a mere man, begged God (not himself) to be spared from crucifixion. This shows the very humanistic nature of Jesus. Actually, he was not begging himself, but begging God out of real fear of a long, agonizing death on the cross.