Prayer of Faith

He knew what He would face.
Luke 22:43 says: And there appeared an angel unto him from Heaven, strengthening him. He needed help to face what He would go through. We need to rely on God to help us when we need it.
Luke 22:44 says: And being in an agony he prayed more earnestly: and his sweat was as it were great drops of blood falling down to the ground. He was in stress beyond anything any of us have been through and His solution was to pray.

Philippians 2:5-8 says: Let this mind be in you, which was also in Christ Jesus: Who, being in the form of God, thought it not robbery to be equal with God: But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men: And being found in fashion as a man, he humbled himself, and became obedient unto death, even the death of the cross.

He accepted the position and circumstances that God the Father put Him in. He did not demand that He receive His rightful position but humbled himself. No matter what we go through, it is only for a short time.
He became obedient unto death, even the death of the cross. He was living as a literal physical man and knew that God the Father knew and understood things that even he did not know and understand. He demonstrated true Biblical faith by His obedience no matter what was the command.
We are commanded to have the same mind. which is the same way of thinking and the same attitude.

Paul continues with the results which Jesus received in Philippians 2:9-11, which says: Wherefore God also hath highly exalted him, and given him a name which is above every name: That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth; And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father.
Paul then follows that up with the application to our lives in Philippians 2:12-13, which says: Wherefore, my beloved, as ye have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling. For it is God which worketh in you both to will and to do of his good pleasure. We are commanded to do work based upon the belief that it is God which worketh in you both to will and to do of his good pleasure. God decides what is best even if it is a death on the cross.

Before this prayer of Jesus, we read that Jesus prayed for Peter in Luke 22:32 (But I have prayed for thee, that thy faith fail not: and when thou art converted, strengthen thy brethren.).

The prayer of Jesus was that Peter's personal faith would nor fail.
Peter's faith failed because he was in denial of what he had been told. He refused to accept God's will. He denied Jesus three times and then, after the resurrection he lead others to return to their job in the world of fishing for fish.
Jesus was conceived as a literal physical man. He lived as a literal physical man. He died as a literal physical man. He prayed as a literal physical man.
The faith of Jesus did not fail Him because He accepted whatever God brought into His life. Peter's faith failed him because he denied truth that God showed him and he refused to accept what God did in his life.
We are commanded to pray in faith. Whatever is going on in your life, if yoyu deny God's truth and reject what God does in your life then your faith and prayer will fail. If you accept whatever God does in your life then your faith and prayer will succeed.