From St. Athanasius the Great, written 333AD
4. Now our life, my brethren, truly consists in our denying all bodily things, and continuing steadfast in those only of our Saviour. Therefore the present season requires of us, that we should not only utter such words, but should also imitate the deeds of the saints. But we imitate them, when we acknowledge Him who died, and no longer live unto ourselves, but Christ henceforth lives in us; when we render a recompense to the Lord to the utmost of our power, though when we make a return we give nothing of our own, but those things which we have before received from Him, this being especially of His grace, that He should require, as from us, His own gifts. He bears witness to this when He says, 'My offerings are My own gifts. ' That is, those things which you give Me are yours, as having received them from Me, but they are the gifts of God.