Question: Should I confront my christian friends who lack convictions, or who have convictions about preferences?
If rebelliousness and a clear pattern of disobedience to Scripture continues after lovingly, consistently sharing where they have deviated from God’s Word, then a careful confronting should ensue (see Matt 18).
Be careful to have objective evidence of a pattern of clear sin that is supported by Scripture.
So “confronting” is almost always tied to willful, unrepentant sin. On the other hand, “compromise” or lack of “biblical conviction” can be a sin (a sin of omission — not doing what Scripture clearly commands us to do). In that case, I would follow what the Lord did with Peter’s denial of him (a major compromise!!) and lovingly discuss how to step-up and avoid these types of omissions. Encourage them through the Word and present a living example of “how” the Lord helped you build and practice biblical convictions in a world that ridicules our faith and often hates our witness for Christ (Matt 5:1-12).
Finally, if someone is making a preference a biblical conviction, then scroll down on this blog until you see the post on “legalism.” That post addresses this problem in a helpful, detailed way! (However the one who posted that article needs a lot of help from what I hear!)