Paul talks to one of his disciples, Timothy, about knowing how people ought to conduct themselves in God's household - the church of the living God. 3:15.
Behaviour is based on belief.
We act out what we believe.
The following letters are known as the 'pastoral epistles' as they are written to ministers in charge of important churches.
These are explicit directions for shepherding the sheep and guarding the churches.
Paul is warning his young disciples against all those things that would weaken or destroy the local church. He addresses false teaching in chapter 1. Directions for the church in 2-3. Directions for the pastor in 4-6.
Paul knew that he would soon die and go to be with the Lord. In the meantime, he entrusted Timothy with the government and supervision of Ephesus and Titus, as the Bishop of Crete. Titus had been successful dealing with the issues in Corinth and Paul was confident he could help at Crete.
Titus can be summed up as Life.
-leave the old life.
-live the new life.
-look for the blessed hope and glorious appearing of Christ Jesus. 2:11-13
Timothy was a young man who was open to receive advice from an older, experienced elder.
Paul had to contend with the passions of youthful thinking in Gentile culture - things like sport and he advises Timothy that, "Physical training is of some value, but godliness has value for all things, holding promise for both the present life and the life to come." 4:8
Next Jude and Peter warn about true and false religion.