3 In a word, let the man who would follow learn the road by which he must travel. Perhaps an hour of terrible trial has come, and the choice is set before you either to do iniquity or endure suffering; the weak soul is troubled, on whose behalf the invincible soul [of Jesus] was voluntarily troubled; set then the will of God before your own. For notice what is immediately subjoined by your Creator and your Master, by Him who made you, and became Himself for your teaching that which He made; for He who made man was made man, but He remained still the unchangeable God, and transplanted manhood into a better condition. Listen, then, to what He adds to the words, “Now is my soul troubled.” “And what shall I say? Father, save me from this hour: but for this cause came I unto this hour. Father, glorify Your name.” He has taught you here what to think of, what to say, on whom to call, in whom to hope, and whose will, as sure and divine, to prefer to your own, which is human and weak. Imagine Him not, therefore, as losing anything of His own exalted position in wishing you to rise up out of the depths of your ruin. For He thought it meet also to be tempted by the devil, by whom otherwise He would never have been tempted, just as, had He not been willing, He would never have suffered; and the answers He gave to the devil are such as thou also ought to use in times of temptation. And He, indeed, was tempted, but not endangered, that He might show you, when in danger through temptation, how to answer the tempter, so as not to be carried away by the temptation, but to escape its danger. But when He here said, “Now is my soul troubled;” and also when He says, “My soul is sorrowful, even unto death;” and “Father, if it be possible, let this cup pass from me;” He assumed the infirmity of man, to teach him, when thereby saddened and troubled, to say what follows: “Nevertheless, Father, not as I will, but as You will.” For thus it is that man is turned from the human to the divine, when the will of God is preferred to his own. But to what do the words “Glorify Your name” refer, but to His own passion and resurrection? For what else can it mean, but that the Father should thus glorify the Son, who in like manner glorifies His own name in the similar sufferings of His servants? Hence it is recorded of Peter, that for this cause He said concerning him, “Another shall gird you, and carry you whither you would not,” because He intended to signify “by what death he should glorify God.” Therefore in him, too, did God glorify His name, because thus also does He glorify Christ in His members.
4. “Then came there a voice from heaven, [saying], I have both glorified it, and will glorify it again.” “I have both glorified it,” before I created the world, “and I will glorify it again,” when He shall rise from the dead and ascend into heaven. It may also be otherwise understood. “I have both glorified it,”— when He was born of the Virgin, when He exercised miraculous powers; when the Magi, guided by a star in the heavens, bowed in adoration before Him; when He was recognized by saints filled with the Holy Spirit; when He was openly proclaimed by the descent of the Spirit in the form of a dove, and pointed out by the voice that sounded from heaven; when He was transfigured on the mount; when He wrought many miracles, cured and cleansed multitudes, fed so vast a number with a very few loaves, commanded the winds and the waves, and raised the dead—“and I will glorify it again;” when He shall rise from the dead; when death shall have no longer dominion over Him; and when He shall be exalted over the heavens as God, and His glory over all the earth.
5. “The people therefore that stood by, and heard it, said that it thundered: others said, An angel spoke to Him. Jesus answered and said, This voice came not because of me, but for your sakes.” He thereby showed that the voice made no intimation to Him of what He already knew, but to those who needed the information. And just as that voice was uttered by God, not on His account, but on that of others, so His soul was troubled, not on His own account, but voluntarily for the sake of others.
Source: Tractates on the Gospel of John (New Advent)