There’re people who debate whether this means there’s “real jews” vs. the Synagogue of Satan, but I’m not hung up on the exact detail of where the boundary is. The one thing all “jews” have in common, is rejection of Christ, right up until very recent times. Affirming Christ as Messiah was the one *guaranteed* way to be rejected by the jewish community. Anyone who embraced Christ would lose their “jewish” identity completely within a generation or two. The modern phenomenon of “Messianic Judaism”, wherein biological jews become some sort of Protestant Evangelicals, only became a thing in the second half of the 20th Century. Most earlier conversions, and subsequent shedding of jewish identity, was towards Orthodoxy and/or Catholicism, though I’m sure there were probably also some Lutherans, Calvinists, etc after the 16th Century. In all cases, the standard (only, really) mechanism by which a person could become “not-a-jew” was through Christianity. Therefore, I’m comfortable asserting the identity between “jews” and “the body of satan”.