2Ti 4:2 (TNIV) Preach the word; be prepared in season and out of season; correct, rebuke and encourage—with great patience and careful instruction.
The word most often translated preach is Kerusso and sadly it doesn’t convey our modern concept of preaching. It simply means to proclaim something, to announce it.
Alan Knox has written a couple of great posts on the subject.
Just Semantics (preach)
Preaching in the Old Testament: Introduction
Preaching in the Old Testament: Genesis-Micah
Preaching in the Old Testament: Joel-Daniel
Preaching in the Old Testament: Conclusion
The NRSV and HCSB get 2Ti 4:2 right on this point as they render Kerusso proclaim rather than preach.
Sadly we read the scriptures through the lens of conventional church experience. We look at 2Tim 4:2 and assume that Timothy is standing up in front a crowd of people who are listening silently. Be prepared in season and out of season means keep a good sermon in your back pocket.
Looking at this passage assuming Timothy is in a house church, which he would have been, it looks a lot different. Being prepared to proclaim the word meant to be ready in every potential interaction to bring the scriptures in to the conversation. Be patient with it, you have to earn peoples trust before you can challenge people deeply. Use careful instruction by gently moving people away from the self-destructive concepts they have in their head. Stay faithful to the truth of the gospel. Be ready to correct, rebuke and encourage people along the way.
The word is best proclaimed in a relationship of mutual love and trust.