Learning from the priests & Levites

The priests and Levites who come to John the Baptist in John 1:19-28 are not interrogators, but inquirers. As servants of the Temple, they are experts in Biblical worship, and in John's practice of baptism, they recognize a new ritual. Notice that they don't challenge baptism's propriety or John's right to perform it; in fact, they seem to implicitly grant it. Instead, they want to understand what this ritual reveals about John's identity.

John the Baptist could be Elijah, who they thought would inaugurate the eschatological Day of the Lord (Malachi 4:5-6). He could be the Christ, who would defeat the enemies of God and his people and establish a reign of eternal peace (Psalms 2 & 45). He could be the Prophet like Moses who will bring a new, perfect and final Law (Deuteronomy 18:15-18). In other words, John the Baptist appears to be a, if not the, subject of prophecy who will inaugurate the eschaton precisely because he has introduced an new ritual which signifies citizenship in a kingdom and entrance into a new age.

Of course, John is merely the herald of that figure. But as he does not challenge the priests' & Levites' assumptions, he effectively affirms them. By so doing, he lets us know that we all could learn a lot from the liturgical expertise of the priests and Levites.