How that the Christ must suffer (ei pathētos ho Christos). Literally, “if the Messiah is subject to suffering.” Ei can here mean “whether” as in Heb 7:15. This use of a verbal in ̇tos for capability or possibility occurs in the N.T. alone in pathētos (Robertson, Grammar, p. 157). This word occurs in Plutarch in this sense. It is like the Latin patibilis and is from paschō. Here alone in N.T. Paul is speaking from the Jewish point of view. Most rabbis had not rightly understood Isa 53:1-12. When the Baptist called Jesus “the Lamb of God” (Joh 1:29) it was a startling idea. It is not then “must suffer” here, but “can suffer.” The Cross of Christ was a stumbling-block to the rabbis.
How that he first by the resurrection of the dead (ei prōtos exō anastaseōs nekrōn). Same construction with ei (whether). This point Paul had often discussed with the Jews: “whether he (the Messiah) by a resurrection of dead people.” Others had been raised from the dead, but Christ is the first (prōtos) who arose from the dead and no longer dies (Rom 6:19) and proclaims light (phōs mellei kataggellein). Paul is still speaking from the Jewish standpoint: “is about to (going to) proclaim light.” See Act 26:18for “light” and Luk 2:32.
Both to the people and to the Gentiles (tōi te laōi kai tois ethnesin). See Act 26:17. It was at the word Gentiles (ethnē) that the mob lost control of themselves in the speech from the stairs (Act 22:21.). So it is here, only not because of that word, but because of the word “resurrection” (anastasis).