Cyril of Alexandria

About the day of the holy Pentecost, Angels coming down from heaven used to trouble the water of the pool, then they would make the plash therefrom the herald of their presence. And the water would be sanctified by the holy spirits, and whoever was beforehand of the multitude of sick people in getting down, he would come up again disburdened of the suffering that troubled him,, yet to one alone, him who first seized it, was the might of healing meted out. …

Commentary on the Gospel of John, Book 2 ↗

Theophylact of Ohrid

What then does he do? He answers very meekly. "Yes," he says, "Lord, I desire to, but I have no man to put me into the water." He utters no blasphemy, he does not reject Christ as having asked an inappropriate question, he does not curse the day of his birth, as we, the fainthearted, do, and that in far lighter illnesses, but he answers meekly and timidly. …

Commentary on John ↗

Thomas Aquinas

Then (v 7), the answer of the sick man is given. Two reasons are given for the length of his illness: his poverty and his weakness. As he was poor, he could not afford a man to plunge him into the pool; so he says, Sir, I have no one to plunge me into the pool. Perhaps he thought, as Chrysostom says, that Christ might even help to put him into the water. Someone else always reached the pool before him because he was weak and not able to move fast; so he says, By the time I get there, someone else has gone in before me. …

Commentary on John ↗

Bonaventure

"The sick man answered him: Lord, I have no man, so that when the water is stirred, he might put me into the pool": and so I am destitute, and there is none to help: the Psalm: "Trouble is near and there is none to help," and I of myself am powerless. Whence he adds: "While I am coming, another descends before me": and so I cannot be healed, because only one is healed, and that the one who descends first. And thus the necessity of the sick man is indicated.

Commentary on John, Chapter 5 ↗