Paul wraps up chapter one much the same as he started it in 1.3, urging and charging.
18 This charge I entrust to you, Timothy, my child, in accordance with the prophecies previously made about you, that by them you may wage the good warfare, 19 holding faith and a good conscience. By rejecting this, some have made shipwreck of their faith, 20 among whom are Hymenaeus and Alexander, whom I have handed over to Satan that they may learn not to blaspheme.
Where we read charge, this is a military word so Paul is being serious, and this takes us back to v.3,
3 As I urged you when I was going to Macedonia, remain at Ephesus so that you may charge certain persons not to teach any different doctrine, 4 nor to devote themselves to myths and endless genealogies, which promote speculations rather than the stewardship from God that is by faith.
Paul is also being loving as he writes Timothy, my child, but overall the message is clear – you need to make sure that what is being taught and accepted as right and proper is, in fact, right and proper.
The tools needed, the weapons needed to wage the good warfare are, we read, faith and a good conscience. They’re pretty essential to our Christian life, aren’t they, faith and a good conscience. We see the consequence of rejecting these fundamentals (v.20), but where does the focus of both lead us?
Faith and a good conscience both lead us to Jesus.
It is through faith in Him that we are saved unto eternal life (Ephesians 2.8-9), and it is through His shed blood for us that our consciences are made good (Hebrews 9.13-14).
So, how do we fight the good fight? With faith and a good conscience.
Where do they lead us? To Jesus.