The letters of Paul to Timothy were written when Paul was advanced in years and he was writing to a much younger Timothy. Paul gave pastoral advice and encouragement in ministry with detailed instructions for church organization and life.
First Letter to Timothy 6:1 Those who are under the yoke of slavery must regard their masters as worthy of full respect, so that the Name of God and our teaching may not suffer abuse.
Second Letter to Timothy 2:19 Nevertheless, God’s solid foundation stands, bearing this inscription, “The LORD knows those who are His”; and “Let everyone who calls upon the Name of the LORD avoid evil.”
The next two letters contain no references to the Name of the LORD and that completes the letters written by St. Paul.