Catena Aurea on John 15:4–7: Augustine of Hippo

But lest any should suppose that a branch could bring forth a little fruit of itself, He adds, For without Me ye can do nothing. He does not say, ye can do little. Unless the branch abides in the vine, and lives from the root, it can bear no fruit whatever. Christ, though He would not be the vine, except He were man, yet could not give this grace to the branches, except He were God.