1 Thessalonians 2:1-12 is all about leadership, though it is often overlooked as a leadership passage in the NT.
I’ve copied the passage below and inserted some comments in italics as I go.
For you yourselves know, brethren, that our coming to you was not in vain, but after we had already suffered and been mistreated in Philippi, as you know, we had the boldness in our God to speak to you the gospel of God amid much opposition.
So leadership is willing to proceed amidst much opposition, and is bold.
For our exhortation does not come from error or impurity or by way of deceit;
So leaders are truthful, open, and straight talking. They don’t try to hide or conceal or trick people or spin things, or try to “justify” such measures as “necessary politics.” Leaders also speak truth, not error—that is, they should not even be unintentionally mistaken about critical issues, especially the gospel. Neither should their motives be for their own gain or otherwise impure.
but just as we have been approved by God to be entrusted with the gospel, so we speak, not as pleasing men but God, who examines our hearts.
Leaders seek to please God, not men. This shows the necessity of pure inward motives, for God examines the heart.
For we never came with flattering speech, as you know,
Again, leaders don’t “spin” things. They don’t give people a sense that they’ve been “sold” or that they aren’t stating the whole truth. They don’t flatter, which is to give insincere compliments or compliments for the sake of personal gain. They lead through the truth, not manipulation.
nor with a pretext for greed—God is witness—nor did we seek glory from men, either from you or from others,
Again, leaders don’t lead for the sake of enriching themselves or receiving glory from people. This is because (see above) they seek the approval of God, not man, and God knows and examines the heart.
even though as apostles of Christ we might have asserted our authority.
Leaders do not by default seek to exert their authority. Their aim is to serve and build up the other, not lord it over those whom they are leading (cf. Matthew 20:25-28). They seek to primarily lead through influence, not the direct exercise of their authority.
But we proved to be gentle among you, as a nursing mother tenderly cares for her own children.
Leaders are not overly critical, and they don’t tear down their people. They exercise gentleness and are encouraging and upbuilding.
Having thus a fond affection for you,
Leaders love their people!
We were well-pleased to impart to you not only the gospel of God but also our own lives, because you had become very dear to us.
The notion that leaders should not be friends with the people they lead is pretty bad. Since leaders love their people, they also share their lives with them.
For you recall, brethren, our labor and hardship, how working night and day so as not to be a burden to any of you, we proclaimed to you the gospel of God.
This echoes the fact that Paul was not out for gain. He worked so as not to require support from them.
You are witnesses, and so is God, how devoutly and uprightly and blamelessly we behaved toward you believers;
Leaders have integrity and are upright and of high character.
just as you know how we were exhorting and encouraging and imploring each one of you as a father would his own children,
Again, leaders exhort and encourage primarily, rather than control. Paul’s leadership is not authoritarian. It is not about making the leader look good, but rather building people up. He leads primarily through influence, not control. He doesn’t motivate through fear and guilt, but through exhortation and encouragement.
So that you may walk in a manner worthy of the God who calls you into His own kingdom and glory.
The goal of spiritual leadership is that people are built up and living lives that reflect the gospel and the greatness of God. Leadership also points people to the future, which is ultimately the coming of God’s kingdom in its fullness and the restoration of all things.