“The fact that many churches avoid uncomfortable topics, not only in the preaching of the Word but in Bible study as well, leads to the creation of blind spots in the theology of even the most devout Christians. These blind spots can then function as a door through which false teaching is introduced; hence the importance of doing as Paul said, preaching the ‘whole counsel of God’ (Acts 20:27 ESV).” (James White, Scripture Alone, Bethany House, Minneapolis, MN, 2004, p95)
Of course, this happens when a pastor does not have the confidence to preach through the Bible in an expository manner, and rather chooses topics to preach on each Sunday or maybe over a period of a few months. This way the pastor can easily skip difficult parts of the text, or passages of Scripture that he does not agree with.