THIS letter from Paul is different from the ones we have studied so far in that this one is addressed to an individual rather than to an entire congregation of saints. Paul was a mentor to many other preachers. One of them was the man whose name this book bears: Timothy. This epistle (or letter) to Timothy begins appropriately with a strong call to sound doctrine. It does matter what we believe. As a minster of the gospel of Jesus Christ, Timothy was responsible for the proclamation of the truth, and for the condemnation of error (vs. 18-20). It takes both.
There is no doubt that Paul and Timothy had one primary thing in common: they were both loyal followers of Jesus Christ, our Savior (vs. 17). But is that all that needs to be said? There are so many people within the realm of Christendom who can't agree on hardly anything (beyond the identity of Christ). While knowing Christ is certainly all we need for salvation (1st John 5:12), there are so many other good spiritual truths to relish and to share (Romans 8:32). Christ is all we need, but the particulars of that word "all" do actually matter. Hence, Pauls’ strict warning against false teachers and their lies. Satan is the ultimate source of bad doctrine. It was his manipulation of God's words that led to the fall of mankind in the Garden of Eden. It was his twisting of the Scripture that permeated the temptation of Christ in the wilderness. And, it has been his meddling hand that has pushed countless "Christian" denominations further and further away from biblical truth (some even into cultism).