Athanasius of Alexandria

Therefore the Image of the unalterable God must be unchangeable; for "Jesus Christ is the same yesterday, today and forever." And David in the psalm says of him, "You, Lord, in the beginning have laid the foundation of the earth, and the heavens are the work of your hands. They shall perish, but you remain; and they all shall grow old as does a garment. And you shall fold them up as a piece of clothing, and they shall be changed, but you are the same, and your years shall not fail." And the Lord says of himself through the prophet, "See now that I, even I am he," and "I change not."