Why in Matthew 26:39 did Jesus beg God to have mercy on him and kill him, before he went through the pain of crucifixion?

This is what Jesus said, “My Father, if it be possible, let this cup pass from me; nevertheless, not as I will, but as you will.” In no way is Jesus asking the Father to kill him. Jesus did not want to go through the excruciating pain and suffering that he was forced to endure on the cross. Who would? That he did not want to go to the cross serves as evidence that he is human, but does not deny his divinity.