John Wesley on Luke 20:38

He is not a God of the dead, or, there is no God of the dead - That is, tho term God implies such a relation, as cannot possibly subsist between him and the dead; who in the Sadducees' sense are extinguished spirits; who could neither worship him, nor receive good from him. So that all live to him - All who have him for their God, live to and enjoy him. This sentence is not an argument for what went before; but the proposition which was to be proved. And the consequence is apparently just. For as all the faithful are the children of Abraham, and the Divine promise of being a God to him and his seed is entailed upon them, it implies their continued existence and happiness in a future state as much as Abraham's. And as the body is an essential part of man, it implies both his resurrection and theirs; and so overthrows the entire scheme of the Sadducean doctrine.