What does Matthew 20:26 mean?
The disciples were in conflict about who among them would be the greatest in Jesus' kingdom. Peter may have seemed to have the inside track (Matthew 16:17), but James and John had just made a play for the top spots in the organization (Matthew 20:20–23). Everyone else was fuming (Matthew 20:24).Jesus has pointed out that this is a very Gentile-style attitude toward power and authority. That's partly a use of the disciples' Jewish sense of spirituality, as well as a statement of fact. Roman rulers, especially, demanded their right to be served and respected by those under their command. They flaunted their superior status. Jesus now says this won't work for His disciples. Power struggles are not the way of the kingdom of heaven (Philippians 2:3).
What's fascinating, though, is that Jesus does not tell His disciples to give up on the ambition to be great. He does not even tell them to stop competing for the position of "greatest." Instead, Jesus tells them how to win—He gives practical advice on how to excel in this godly "race" (1 Corinthians 9:24). If you want to be great, Jesus says you must become a servant (John 13:12–17).
Of course, this would have sounded like nonsense to first-century ears. Servants were, by definition, the opposite of great. In this culture, humility was not a virtue; it was the result of weakness. The Greek word for servant, diakonos, usually referred to a hired worker, especially one who helped to maintain another person's household. Servants received commands from greater men; they didn't give them. Servants might be nice people, but they were nobodies. In fact, in the ancient world, it was assumed that rulers and royalty were literally better people than servants and subjects, and that's why each was born into that status.
Rather than clarifying this startling declaration, Jesus simply reemphasizes it in the following verse.