Origen — as excerpted in the Catena Aurea on Matthew 26:39-44

“He took with Him the self-confident Peter, and the others, that they might see Him falling on His face and praying, and might learn not to think great things, but little things of themselves, and not to be hasty in promising, but careful in prayer. And therefore, He went forward a little, not to go far from them, but that He might be near them in His prayer. Also, He who had said above, Learn of me, for I am meek and lowly in heart, now commendably humbling Himself, falls on His face. But He shews His devotion in His prayer, and as beloved and well-pleasing to His Father, He adds, Not as I will, but as thou wilt, teaching us that we should pray, not that our own will, but that God’s will, should be done. And as He began to have fear and sorrow, He prays accordingly that the cup of His Passion may pass from Him, yet not as He wills, but as His Father wills; wills, that is, not according to His Divine and impassible Substance, but according to His human and weak nature. For in taking upon Him the nature of human flesh, He fulfilled all the properties thereof, that it might be seen that He had flesh not in appearance only, but in-reality. The believer indeed must in the first instance be loth to incur pain, seeing it leads to death, and he is a man of flesh; but if it be God’s will, he acquiesces because he is a believer. For as we ought not to be too confident that we may not seem to make a boast of our own strength; so neither ought we to be distrustful, lest we should seem to charge God our helper with weakness. It is to be observed that Mark and Luke write the same, but John does not introduce this prayer of Jesus’, that this cup may pass from Him, because the first three are rather occupied about Him, according to His human nature, John according to His divine. Otherwise; Jesus makes this petition, because He sees what the Jews will suffer for requiring His death.”