Hilary of Poitiers
Catena Aurea · Johannesevangelium 11
And Jesus lifted up his eyes, and said, Father, I thank thee that thou hast heard me. And I knew that thou hearest me always: but because of the people which stand by I said it, that they may believe that thou hast sent me. And when he thus had spoken, he cried with a loud voice, Lazarus, come forth. And he that was dead came forth, bound hand and foot with graveclothes: and his face was bound about with a napkin. Jesus saith unto them, Loose him, and let him go. Then many of the Jews which came to Mary, and had seen the things which Jesus did, believed on him. But some of them went their ways to the Pharisees, and told them what things Jesus had done.
(lib. x. de Trin.) He did not therefore need to pray: He prayed for our sakes, that we might know Him to be the Son: But because of the people which stand by I said it, that they may believe that Thou hast sent Me. His prayer did not benefit Himself, but benefited our faith. He did not want help, but we want instruction.