John 14:13

(Hom. lxxiv. 2) In My name, He says. Thus the Apostles; In the name of Jesus of Nazareth, arise and walk. (Acts 3:6) All the miracles that they did, He did: the hand of the Lord was with them. (Hom. lxxiv. 2) For when the great power of the Son is manifested, He that begat Him is glorified. He introduces this last, to confirm the truth of what He has said.

But if we think it impious to believe that the Father has handed over all judgment to the Son in such a way that he does not have it himself—for he has it and cannot lose what the divine majesty has by its very nature—we ought to consider it equally impious to suppose that the Son cannot give what either men and women can merit or any creature can receive, especially as he himself has said, "I go to my Father, and whatever you shall ask of him in my name, that will I do." For if the Son cannot give what the Father can give, the Truth has lied and cannot do what the Father has been asked for in his name. He therefore did not say, "For whom it has been prepared by my Father," in order that requests should be made only of the Father. For all things that are asked of the Father, [the Son] has declared that he [himself] will give. And finally, he did not say, "Whatever you shall ask of me, that will I do" but "Whatever you shall ask of him in my name, that will I do."

How, then, are we to understand "Whatsoever ye shall ask, I will do it," if there are some things which the faithful ask, and which God, even purposely on their behalf, leaves undone? Or ought we to suppose that the words were addressed only to the apostles? Surely not. For what He has got the length of now saying is in the very line of what He had said before: "He that believeth in me, the works that I do shall he do also; and greater works than these shall he do;" which was the subject of our previous discourse. And that no one might attribute such power to himself, but rather to make it manifest that even these greater works were done by Himself, He proceeded to say, "For I go to the Father; and whatsoever ye shall ask in my name, I will do it." Was it the apostles only that believed on Him? When, therefore, He said, "He that believeth on me," He spake to those, among whom we also by His grace are included, who by no means receive everything that we ask. And if we turn our thoughts even to the most blessed apostles, we find that he who labored more than they all, yet not he, but the grace of God that was with him, besought the Lord thrice that the messenger of Satan might depart from him, and received not what he had asked. What shall we say, beloved? Are we to suppose that the promise here made, "Whatsoever ye shall ask in my name, I will do it," was not fulfilled by Him even to the apostles? And to whom, then, will ever His promise be fulfilled, if therein He has deceived His own apostles?