They also appear in Pliny the Elder's Natural History, together with Moses, as famous magicians of antiquity; Pliny's citation is also referred to in Apuleius. Numerius, a Pythagorean philosopher, calls them sacred Egyptian scribes. Origen says that there was an apocryphal book called The Book of Jannes and Jambres, containing details of their exploits, and that St Paul's epistle was quoting from it. This book has not been rediscovered.
Jewish traditions in the Targums preserve other half-legendary lore about the pair. They are called the sons of Balaam, the unwitting prophet of Pelor. It was also claimed that they converted to Judaism, and that they left Egypt at the Exodus; however, they perished on the way, either at the Red Sea, or the destruction of the Golden Calf, or at the slaughter of Phinehas and his followers.