1 Tim. 6:13-16 (ESV)
I charge you in the presence of God, who gives life to all things, and of Christ Jesus, who in his testimony before Pontius Pilate made the good confession,  to keep the commandment unstained and free from reproach until the appearing of our Lord Jesus Christ,  which he will display at the proper time—he who is the blessed and only Sovereign, the King of kings and Lord of lords,  who alone has immortality, who dwells in unapproachable light, whom no one has ever seen or can see. To him be honor and eternal dominion. Amen.
Keep the commandment unstained. One wonders which commandment he is talking about? From the context of this chapter, it seems it could only be the commandment to keep God’s word pure, not to let it be corrupted for the sake of material gain. This is a high charge. But it is of all importance. Doctrine does infact save. Not that you have to memorize Chemnitz’s “Two Natures in Christ” in order to be saved. But pastors are charged to teach the gospel, teaching is doctrine, It is what doctrine means, teaching. And it is the Gospel that saves, nothing else can.