In proof of the resurrection there were many plainer passages which He might have cited; among others that of Isaiah, “The dead shall be raised; they that are in the tombs shall rise again:” [Isa 26:29, Septuagint] and in another place, “Many of them that sleep in the dust of the earth shall awake.” [Dan 12:2]
It is enquired therefore why the Lord should have chosen this testimony which seems ambiguous, and not sufficiently belonging to the truth of the resurrection; and as if by this He had proved the point adds, “He is not the God of the dead, but of the living.”
We have said above that the Sadducees confessed neither Angel, nor spirit, nor resurrection of the body, and taught also the death of the soul. But they also received only the five boots of Moses, rejecting the Prophets. It would have been foolish therefore to have brought forward testimonies whose authority they did not admit. To prove the immortality of souls therefore, He brings forward an instance out of Moses, “I am the God of Abraham, &c.” and then straight subjoins, “He it not the God of the dead, but of the living;” so that having established that souls abide after death, (forasmuch as God could not be the God of those who had no existence any where,) there might fitly come in the resurrection of bodies which had together with their souls done good or evil.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).