Paul understands he is about to be put to death for holding firmly to the Gospel. Death surrounds this letter. Instead of turning inward, which is understandable, by God's grace, he looks forward.
Corrupt teachers, ministry responsibilities, and suffering are central to how he instructs, warns, and tenderly guides his dear friend and colleague Timothy. Paul knows his life is ending, but the church will not. 2 Timothy is written with this in mind.
Part of guarding the faith is to teach the faith soundly to others. In other words, Discipleship. Paul's pattern for Timothy is the very root of Discipleship. One seasoned Christian building into the life of reliable people to glorify Christ, practice sound doctrine, and grow in grace so that they will, in time and turn, disciple others.