Jesus could not come down from the cross anytime He wanted. Jesus was a human man. He had emptied Himself of all His Godly powers when He became a human. Jesus did not do any miracles or have any special powers. All His works were done by the Father. The Father could have brought Jesus down from the cross, but Jesus Himself had no such supernatural powers.
John it is quite obvious as you say that all of Jesus' works were done by the Father, but that was true before He was a man and is now as well... His power is always from the Father, so it a matter of how you look at it I suppose.
1Cor 8:6 yet for us there is one God, the Father, of whom are all things, and we for Him; and one Lord Jesus Christ, through whom are all things, and through whom we live.
Jesus did say to His disciples that He could pray to the Father and He would provide Him all the help He needed... so I think He actually could have come down from the cross if He desired to.
Mat 26:52 But Jesus said to him, "Put your sword in its place, for all who take the sword will perish by the sword.
v. 53 Or do you think that I cannot now pray to My Father, and He will provide Me with more than twelve legions of angels?
v. 54 How then could the Scriptures be fulfilled, that it must happen thus?"
To say that He had no Godly powers... well how was He God then? He most certainly was God and had great power as is witnessed in many Scripture.
Mat 21:19 And seeing a fig tree by the road, He came to it and found nothing on it but leaves, and said to it, "Let no fruit grow on you ever again." Immediately the fig tree withered away.
He did not need to pray to the Father for this to happen, He did it, and yes by the power/Holy Spirit from the Father in Him. There is also when the woman was healed "Jesus, immediately knowing in Himself that
power had gone out of Him."
Mark 5:25 Now a certain woman had a flow of blood for twelve years,
v. 26 and had suffered many things from many physicians. She had spent all that she had and was no better, but rather grew worse.
v. 27 When she heard about Jesus, she came behind Him in the crowd and touched His garment.
v. 28 For she said, "If only I may touch His clothes, I shall be made well."
v. 29 Immediately the fountain of her blood was dried up, and she felt in her body that she was healed of the affliction.
v. 30 And Jesus, immediately knowing in Himself that power had gone out of Him, turned around in the crowd and said, "Who touched My clothes?"
Another thing is He was literally walking on the water and called Peter to walk on it too.
Mat 14:26 When they saw him walking on the water, they were terrified. "It's a ghost!" they said, and screamed with fear.
v. 29 "Come!" answered Jesus. So Peter got out of the boat and started walking on the water to Jesus.
Also Jesus could read the thoughts in peoples minds.
Mark 2:6 And some of the scribes were sitting there and reasoning in their hearts,
v. 7 "Why does this Man speak blasphemies like this? Who can forgive sins but God alone?"
v. 8 But immediately, when Jesus perceived in His spirit that they reasoned thus within themselves, He said to them, "Why do you reason about these things in your hearts?
Mat 12:24 Now when the Pharisees heard it they said, "This fellow does not cast out demons except by Beelzebub, the ruler of the demons."
v. 25 But Jesus knew their thoughts, and said to them: "Every kingdom divided against itself is brought to desolation, and every city or house divided against itself will not stand.
Luke 9:47 And Jesus, perceiving the thought of their heart, took a little child and set him by Him,
v. 48 and said to them, "Whoever receives this little child in My name receives Me; and whoever receives Me receives Him who sent Me. For he who is least among you all will be great."
John 10:30 I and My Father are one.
He is one with the Father with the power of God, this was always the case, during His His time on earth as He said there and of course before and after as well.
mercy, peace and love
Kat