Jesus called them together and said, “You know that the rulers of the Gentiles lord it over them, and their high officials exercise authority over them. 26 Not so with you. Instead, whoever wants to become great among you must be your servant, 27 and whoever wants to be first must be your slave— 28 just as the Son of Man did not come to be served, but to serve, and to give his life as a ransom for many.” - Matthew 20:25-28
The Greek word translated "lord over" is κατακυριεύω. It means to subdue, coerce, overpower someone. In contrast, Jesus knows leadership has power, but it is not used for self but for others. In other words, Christian leaders empower others and use whatever position or gift they have for the sake of serving the whole.