The Christmas Classroom.
We live in a culture of self-indulgence. Because of the pervasive influence of sin, humanity can't help but ruin ourselves even if we intend to do right. Titus 1:10-16 illustrates that Paul was writing to a pastor ministering in a similar society. False religious teachers in Crete had head knowledge of God without true heart knowledge, so their actions were ungodly. Both religious and irreligious people miss the mark because they seek to do things their own way.
Humanity left to itself always brings its own ruin personally and corporately. Paul's letter to Titus presents the solution: a body of true believers led by a good pastor-shepherd and sound doctrine taught by older examples.