“Elchasaites” (or “Elkesaites”) is a scholarly designation for ancient groups of Jews who believed in Jesus (Jewish Christians). They possessed a postbiblical book with revelations that was somehow connected with the name Ἠλχασαι or Ἠλξαι/Ἠλξαιος. The evidence is fragmentary and far from univocal and has given rise to very different source-critical and historical hypotheses.

The earliest two sources, the Refutation of all Heresies, composed in about 230 CE by Hippolytus of Rome, and a sermon on Ps 82 delivered by Origen in Caesarea b…