It should be further considered, that this was said to Moses at a time when those holy Patriarchs had gone to their rest. They therefore of whom He was the God were in being; for they could have had nothing, if they had not been in being; for in the nature of things that, of which somewhat else is, must have itself a being; so they who have a God must themselves be alive, since God is eternal, and it is not possible that which is dead should have that which is eternal. How then shall it be affirmed that those do not, and shall not hereafter, exist, of whom Eternity itself has said that He is?
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).