As a professor, I’m often asked by students to write letters of recommendation for them—for leadership positions, study-abroad programs, graduate schools, and even jobs. In each letter, I have a chance to praise the student’s character and qualifications.

When Christians traveled in the ancient world, they often carried with them similar “letters of commendation” from their churches. Such a letter ensured that the traveling brother or sister would be welcomed hospitably.

The apostle Paul didn’t need a letter of recommendation when he spoke to the church in Corinth—they knew him. In his second letter to that church, Paul wrote that he preached the gospel out of sincerity, not for personal gain (2 Corinthians 2:17). But then he wondered if his readers would think that in defending his motives in preaching, he was trying to write a letter of recommendation for himself.

He didn’t need such a letter, he said, because the people in the church in Corinth were themselves like letters of recommendation. The visible work of Christ in their lives was like a letter “written not with ink but with the Spirit of the living God” (3:3). Their lives testified to the true gospel Paul had preached to them—their lives were letters of reference that could be “known and read by everyone” (3:2). As we follow Jesus, this becomes true of us too—our lives tell the story of the goodness of the gospel.