Catena Aurea on John 15:4–7: John Chrysostom

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.