John Calvin Commentary 2 Timothy 2:18

"men who concerning the truth have erred, saying that the resurrection is past already, and overthrow the faith of some." — 2 Timothy 2:18 (ASV)

Who, concerning the truth have erred, saying that the resurrection is already past. After saying that they had departed from “the truth,” he specifies their error, which consisted in this: they claimed that “the resurrection was already past.” In doing this, they undoubtedly contrived a sort of allegorical resurrection, which has also been attempted in this present age by some filthy dogs.

By this trick Satan overthrows that fundamental article of our faith concerning the resurrection of the flesh. Being an old and worthless dream, and being so severely condemned by Paul, it should cause us less concern. But when we learn that, from the very beginning of the gospel, the faith of some was subverted, such an example should spur us to diligence, so that we may act promptly to drive away from ourselves and others such a dangerous plague. For, because of people's strong inclination towards vanity, no absurdity is so monstrous that some people will not lend an ear to it.