2 Timothy 3:8 says : “Now as Jannes and Jambres withstood Moses, so do these also resist the truth: men of corrupt minds, reprobate concerning the faith.” How did Paul know the names of Jannes and Jambres while we can’t find them even in the Old Testament?
A good question. Jannes and Jambres are the traditional names, from Jewish literature, of the two magicians who Moses opposed in Exodus 7:11-12. These names are found in the Jewish Targum of Jonathan and in the Talmud. By the time of Christ everyone associated these names with the Egyptian magicians.
Whether this was in fact the name of the two magicians is doubtful. These are the traditional names. However, the history of Jannes and Jambres being used as the names of the magicians is not sufficiently complete that we can say with any confidence that these are the actual names of the magicians. However, when Paul wrote to Timothy, it was “common knowledge” to Jews such as Timothy, so we can assume that he knew exactly who Paul was referring to in 2 Tim 3:8. Paul is comparing the magicians who opposed Moses before Pharaoh to the false teachers that will come up from within the church to oppose the true gospel teaching.