Here's strong language used to address young, perhaps timid Timothy. If he would be a good servant of Christ, he must command and teach.
The word "command" here is striking to modern ears. Ours is a culture that recoils at authority, especially authority coupled with certainty and strength. We would rather a "leader" who is a "facilitator," a "consensus builder" or a "motivator." And all these things have their place in the armament of leadership; there will be times when a soft approach is best, when nurturing one-mindedness is not only palatable but essential to the task of moving a group to a desired end.
But that's not the tone the apostle strikes for Timothy here. He says "command... these things." There is to be a note of authority in Timothy's interaction with his congregation.
To be sure, Paul is not here violating the teaching of our Lord when He says that we are not to "lord it over" one another (Luke 22:25-26). He isn't encouraging Timothy to establish a little dictatorship inside the church wherein he governs with an iron glove. The saints of God will one day rule with Christ who wields an iron sceptre (Rev. 2:26-27), but until then military-like conquest and bullying are not the paradigms.
But a good leader does exercise authority. He will command certain things. Christ Jesus taught as one who had authority, not like the scribes, and so are faithful pastors to "command" things, to teach with authority, not like hair-splitting scaredy-cats afraid to land on one side of the fence or the other. A good pastor is to trumpet a clear and certain sound.
The lion's boldness is required in the pastor who would please His Lord. One expression of that boldness is willingness (nay a certain kind of godly delight) in commanding what is right--especially when the things in view (1) are from the Lord and (2) are of great importance. Here, the good pastor must learn that in commanding things, he himself is not the Commander. He is but a messenger and an example, but the commands are not his to develop and distribute at whim. The commands are to be clearly from the Lord. And, the good pastor will major on those things of great importance. The "these things" of verse 11 have to do with the spiritual warfare in which the Christian is engaged and the freedom provided in Christ. "These things" refer to godliness, sound doctrine, and a firm trust in the living God, the Savior of the believers. On these things Timothy and the good pastor is to major.
John Calvin puts it this way:
The doctrine is of such a kind, that men outght not to be weary of it, though they heard it every day. There are, no doubt, other things to be taught; but there is emphasis in the demonstrative these; for it meands that they are not things of small importance, of which it is enough to take a passing and brief notice; but, on the contrary, that they deserve to be repeated every day, because they cannot be too much inculcated. A prudent pastor ought, therefore, to consider what things are chiefly necessary, that he may dwell on them. Nor is there reason to dread that it shall become wearisome; for whosoever is of God will gladly hear frequently those things which need to be so often uttered. (italics added)
Calvin insightfully raises one challenge to our being good pastors in this way: it's that fear of man that whispers to us "your people have already heard this; they grow tired of your always insisting on these things." That's the whisperer's tale. But if you've been an elder or pastor for any length of time, you know that repetition is essential to teaching. Yes they've heard it, but they've not remembered or adopted the teaching in more instances than we care to recount. More often than we like, we all are like that man who looks at his face in the mirror but when he turns away forgets the image he saw.
So, it's not burdensome for us to repeat and to reteach; and, we don't shrink at the faces of men who give outward or spoken disapproval. We "command" these things... because the commands of the Lord are good and not burdensom (1 John 5:3), for the health of the people in our care, and in order to faithfully discharge our duty as good servants of Christ.