Though there is leadership in the Book of Acts, the examples we find are of those who serve the body of Christ. A gathering of believers is still an Assembly even if there is no defined servant leader. As the fellowship grows in the Lord, the Spirit will gift certain men as shepherds.
The 12 Apostles were servants to widows giving them bread daily for a season, until they realized they needed to fully devote themselves to studying the Scriptures and giving themselves to prayer.
They delegated the function of physically serving the widows but expanded their service to the congregation to give them spiritual food. Though a shepherd in the body of Christ has concerns to watch over the Flock, in the Word and prayer, and teaching the body, he must do all in the spirit of servanthood to help others.
To serve others is the example our Lord Jesus gave us when He who was the teacher and rabbi took the form of a servant and washed the feet of His disciples.
When a leader desires honor for his own self; when he wants esteem from men, when he exercises control for gain and power, he is not a leader in the body of Christ. Paul didn’t even exercise authority over Apollos to come to Corinth even though Paul “greatly desired him to come.” Paul allowed the Holy Spirit to guide Apollos in his personal walk when he said, “He was quite unwilling to go now, but he will go when he has the opportunity.”
Overseers also are not to desire preeminence.
In fact, where there are such desires of greatness Jesus gives clear teachings on not taking titles and not lording over others in the body of Christ.
Concluding with this powerful statement for those who would be leaders in His kingdom: “The greatest among you will be your servant. For those who exalt themselves will be humbled, and those who humble themselves will be exalted.”