This is a surprising moment. Up to this point in Matthew, the scribes have not come off well. At the close of the Sermon on the Mount, the crowds were astonished because Jesus “was teaching them as one who had authority, and not as their scribes” (Matthew 7:29). The scribes were the Bible professionals of the day, the people you went to with your hard questions. Now one of them steps out of the crowd and says, in effect, “I’m all in.” There is no reason to think he is faking it. He means it.
But listen to how he addresses Jesus: “Teacher.” Several commentators observe that in Matthew’s Gospel, those who call Jesus “Teacher” are almost always people on the outside of the kingdom, while the disciples call him “Lord.” The title is not wrong. Jesus is a teacher, the greatest who ever lived. But it is accurate without being adequate. You can respect Jesus, quote Jesus, even admire Jesus, and still keep him at the level of a wise rabbi rather than bowing to him as Lord.
There is something else underneath the scribe’s words. In that culture, a would-be disciple chose his rabbi. You listened around, compared teachers, and picked the one you liked. Frederick Dale Bruner notes that the scribe’s offer sounds almost like a favor: this is your lucky day, Jesus; I have decided to be your disciple. But that is not how it works in Matthew. When Jesus called Peter and Andrew, he said, “Follow me” (Matthew 4:19). Jesus is not chosen; Jesus does the choosing. Before we can follow him rightly, we have to surrender the posture of the consumer who is evaluating the options.