Subjects: Qualifications for leadership, We can deny God with our actions, Be godly and self-controlled, The Holy Spirit turns us away from disobedience, etc.
Paul introduces himself to Titus and reminds him that he wanted him to stay in Crete in order to set up the church(es) there, selecting leaders to be in charge of the believers. Paul covers the qualifications for the elders and bishops, essentially saying that they need to be sinless, righteous, and educated in the word of God.
Paul also says that those who are false teachers need to be stopped from spreading their falsehood. Paul tells Titus, "rebuke then sharply, so that they may become sound in the faith, not paying attention to Jewish myths or to [instructions] of those who reject the truth." (Titus 1:13-14)
Speaking of these false teachers, Paul says, "They profess to know God, but they deny him by their actions." (Titus 1:16) This statement is important, because Paul is making it clear that anyone can claim to be a believer, but we can deny God with our actions.
These false teachers likely thought they were saved and that they were actually teaching the truth; however, Paul claims their actions deny God even though they claim otherwise. Essentially, their actions prove what is true, and we show what we truly believe by what we do.
True faith is supported by our righteous actions and abstinence from sin. James says, "For just as the body without the spirit is dead, so faith without works is also dead." (James 2:26) James connects "works" to obeying God's commandments in James 2:8-12.
Paul encourages Titus to instruct with good teachings that are scriptural. He then gives examples of how believers should behave, including being self-controlled. Paul says that God's grace "[trains] us to renounce impiety and worldly passions, and in the present age to live lives that are self-controlled, upright, and godly..." (Titus 2:11-12)
This statement in Titus 2:11-12 is the essence of repentance and Becoming a Mature Christian: training to be self-controlled, upright, and godly.
Paul encourages Titus to be confident in opposing anyone who teaches incorrect doctrine.
Paul continues giving Titus instructions on what to teach and remind the believers. Paul makes the point that "we ourselves were once foolish, disobedient, led astray, slaves to various passions and pleasures...But when the goodness and loving kindness of God our Savior appeared, he saved us, not because of any works of righteousness that we had done, but according to his mercy, through the water of rebirth and renewal by the Holy Spirit." (Titus 3:3-4)
Paul is plainly illustrating the message of the gospel: that we have done nothing to earn salvation, but that God's kindness does cause a change in behavior. Paul notes that "we ourselves were once foolish, disobedient..." but that God's kindness caused rebirth and renewal through faith and repentance.
In Romans 2:4, Paul says, "Do you not realize that
God's kindness is meant to lead you to repentance?"
Paul wants Titus to insist on these facts, "so that those who have come to believe in God may be careful to devote themselves to good works." (Titus 3:8) Paul then tells Titus to avoid anyone who refuses to repent of their focus on worthless obsessions of genealogies, myths, and disagreements in general.
According to Paul, Titus has been left in Crete in order to lay the foundation of the church(es) by electing leaders from the believers in Crete. Paul gives Titus qualifications for the leaders, as well as instructions for all believers in Crete.
The main subjects that Paul covers in this letter to Titus are: Qualifications for leadership, We can deny God with our actions, Be godly and self-controlled, The Holy Spirit turns us away from disobedience, etc.