Augustine of Hippo
Catena Aurea · Johannesevangelium 20
And after eight days again his disciples were within, and Thomas with them: then came Jesus, the doors being shut, and stood in the midst, and said, Peace be unto you, Then saith he to Thomas, Reach hither thy finger, and behold my hands; and reach hither thy hand, and thrust it into my side: and be not faithless, but believing. And Thomas answered and said unto him, My Lord and my God. Jesus saith unto him, Thomas, because thou hast seen me, thou hast believed: blessed are they that have not seen, and yet have believed. And many other signs truly did Jesus in the presence of his disciples, which are not written in this book: But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name. Jesus saith unto him, Because thou hast seen Me, thou hast believed.
(Tr. cxxi) He saith not, Hast touched me, but, hast seen me; the sight being a kind of general sense, and put in the place often of the other four senses; as when we say, Hear, and see how well it sounds; smell, and see how sweet it smells; taste, and see how well it tastes; touch, and see how warm it is. Wherefore also our Lord says, Reach hither thy finger, and behold My hands. What is this but, Touch and see? And yet he had not eyes in his finger. He refers them both to seeing and to touching, when He says, Because thou hast seen, thou hast believed. Although it might be said, that the disciple did not dare to touch, what was offered to be touched.