What does 2 Timothy 2:17 mean?

Giving undue attention to distracting arguments is like introducing a disease into the body of Christ. The disease mentioned here is literally gangrene, a term used by secular writers in the first century regarding a sore that eats at the flesh. Left untreated, it continues to infect more and more parts of the body, spreading further and further. In a similar way, the talk of false teachers spreads throughout a congregation or body of believers, causing much pain. If Luke was involved in writing this letter (2 Timothy 4:11), his use of this precise term would have been intentional.

Paul specifically mentions "Hymenaeus and Philetus" as false teachers. Hymenaeus was certainly the same person mentioned by Paul in 1 Timothy 1:20: "among whom are Hymenaeus and Alexander, whom I have handed over to Satan that they may learn not to blaspheme." Philetus is mentioned only here in the New Testament and may have joined Hymenaeus later as a partner or disciple in his false teachings. Their false teachings are mention in the next verse.