John 15:4

“(Hom. lxxvi. 1) The Son then contributes no less than the Father to the help of the disciples. The Father changeth, but the Son keepeth them in Him, which is that which makes the branches fruitful. And again, the cleansing is attributed to the Son also, and the abiding in the root to the Father who begat the root. (c. 2.). It is a great loss to be able to do nothing, but He goes on to say more than this: If a man abide not in Me, he is cast forth as a branch, i. e. shall not benefit by the care of the husbandman, and withereth, i. e. shall lose all that it desires from the root, all that supports its life, and shall die.”

“(Tract. lxxxi. 1) Abide in Me, and I in you: not they in Him, as He in them; for both are for the profit not of Him, but them. The branches do not confer any advantage upon the vine, but receive their support from it: the vine supplies nourishment to the branches, takes none from them: so that the abiding in Christ, and the having Christ abiding in them, are both for the profit of the disciples, not of Christ; according to what follows, As the branch cannot bear fruit of itself, except it abide in the vine, no more can ye, except ye abide in Me. Great display of grace! He strengtheneth the hearts of the humble, stoppeth the mouth of the proud. They who hold that God is not necessary for the doing of good works, the subverters, not the assertors, of free will, contradict this truth. For he who thinks that he bears fruit of himself, is not in the vine; he who is not in the vine, is not in Christ; he who is not in Christ, is not a Christian.”

“(Tract. lxxxi. 3) 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.”

“(Tract. lxxxi. 4) For then may His words be said to abide in us, when we do what He has commanded, and love what He has promised. But when His words abide in the memory, and are not found in the life, the branch is not accounted to be in the vine, because it derives no life from its root. So far as we abide in the Saviour we cannot will any thing that is foreign to our salvation. We have one will, in so far as we are in Christ, another, in so far as we are in this world. And by reason of our abode in this world, it sometimes happens that we ask for that which is not expedient, through ignorance. But never, if we abide in Christ, will He grant it us, Who does not grant except what is expedient for us. And here we are directed to the prayer, Our Father. Let us adhere to the words and the meaning of this prayer in our petitions, and whatever we ask will be done for us.”

“All the fruit of good works proceeds from this root. He who hath delivered us by His grace, also carries us onward by his help, so that we bring forth more fruit. Wherefore He repeats, and explains what He has said: I am the vine, ye are the branches. He that abideth in Me, by believing, obeying, persevering, and I in Him, by enlightening, assisting, giving perseverance, the same, and none other, bringeth forth much fruit.”