He Will Baptize With the Spirit

I baptize you with water for repentance. But after me will come one who is more powerful than I, whose sandals I am not worthy to carry. He will baptize you with the Holy Spirit and fire. John the Baptist identifies his own limitation and points forward.

There's something about John's self-knowledge here. He knows what he can do (water baptism) and what he can't (Holy Spirit transformation). He positions himself as transitional. Not threatened by being superseded. That's healthy humility—you know your role and don't exceed it.