Matthew 14:30

That when Peter was seized with fear, the Lord gave him not power of coming to Him, but held him by the hand and sustained him, this is the signification thereof; that He who alone was to suffer for all alone forgave the sins of all; and no partner is admitted into that which was bestowed upon mankind by one.

Moreover he is left to temptation for a short season, that his faith may be increased, and that he may understand that he is saved not by his ability to ask, but by the power of the Lord. For faith burned at his heart, but human frailty drew him into the deep.

Or; That Peter alone out of all the number of those that were in the vessel has courage to answer, and to pray that the Lord would bid him come to Him upon the waters, figures the frowardness of his will in the Lord's passion, when following after the Lord's steps he endeavoured to attain to despise death. But his fearfulness shows his weakness in his after trial, when through fear of death, he was driven to the necessity of denial. His crying out here is the groaning of his repentance there.

"And he said, Come. And when Peter was come down out of the ship, he walked on the water, and came to Jesus. But when he saw the wind boisterous, he was afraid; and beginning to sink, he cried, saying, Lord, save me. And immediately Jesus stretched forth His hand and caught him, and saith unto him, O thou of little faith, wherefore didst thou doubt?" This is more wonderful than the former. Therefore this is done after that. For when He had shown that He rules the sea, then He carries on the sign to what is yet more marvellous. Then He rebuked the winds only; but now He both walks Himself, and permits another to do so; which thing if He had required to be done at the beginning, Peter would not have so well received it, because he had not yet acquired so great faith. Wherefore then did Christ permit him? Why, if He had said, "thou canst not," Peter being ardent would have contradicted Him again. Wherefore by the facts He convinces him, that for the future he may be sobered. But not even so doth he endure. Therefore having come down, he becomes dizzy; for he was afraid. And this the surf caused, but his fear was wrought by the wind. Peter then having come down from the ship went unto Him, not rejoicing so much in walking on the water, as in coming unto Him. And when he had prevailed over the greater, he was on the point of suffering evil from the less, from the violence of the wind, I mean, not of the sea. For such a thing is human nature; not seldom effecting great things, it exposes itself in the less; as Elias felt toward Jezebel, as Moses toward the Egyptian, as David toward Bathsheba. Even so then this man also; while their fear was yet at the height, he took courage to walk upon the water, but against the assault of the wind he was no longer able to stand; and this, being near Christ. So absolutely nothing doth it avail to be near Christ, not being near Him by faith. And this also showed the difference between the Master and the disciple, and allayed the feelings of the others. For if in the case of the two brethren they had indignation, much more here; for they had not yet the Spirit vouchsafed unto them. But afterwards they were not like this. On every occasion, for example, they give up the first honors to Peter, and put him forward in their addresses to the people, although of a rougher vein than any of them. And wherefore did He not command the winds to cease, but Himself stretched forth His hand and took hold of him? Because in him faith was required. For when our part is wanting, then God's part also is at a stand. Signifying therefore that not the assault of the wind, but his want of faith had wrought his overthrow, He saith, "Wherefore didst thou doubt, O thou of little faith?" So that if his faith had not been weak, he would have stood easily against the wind also. And for this reason, you see, even when He had caught hold of Him, He suffers the wind to blow, showing that no hurt comes thereby, when faith is steadfast. And as when a nestling has come out of the nest before the time, and is on the point of falling, its mother bears it on her wings, and brings it back to the nest; even so did Christ.

(Serm. 76.) For in one Apostle, namely Peter, first and chief in the order of Apostles in whom was figured the Church, both kinds were to be signified; that is, the strong, in his walking upon the waters; the weak, in that he doubted, for to each of us our lusts are as a tempest. Dost thou love God? Thou walkest on the sea; the fear of this world is under thy feet. Dost thou love the world? It swallows thee up. But when thy heart is tossed with desire, then that thou mayest overcome thy lust, call upon the divine person of Christ.