1 Corinthians 15:20 - Ellicott's Commentary On The Whole Bible

But now... — From the hopeless and ghastly conclusion in which the hypothetical propositions of the previous verse would logically land us, the Apostle turns, with the consciousness of truth, to the hopeful faith to which a belief in the resurrection leads. It cannot be so. Now is Christ risen from the dead. And that is no isolated fact. As the firstfruits were typical of the whole harvest (Leviticus 23:10-11), so is Christ. He rose, not to the exclusion but to the inclusion of all Humanity. If St. Paul wrote this Epistle about the time of Passover (see Introduction, and 1 Corinthians 5:6; 1 Corinthians 16:8), the fact that the Paschal Sabbath was immediately followed by the day of offering of firstfruits may have suggested this thought.