Matthew 3:6

καὶ ἐβαπτίζοντο ἐν τῷ Ἰορδάνῃ ὑπ’ αὐτοῦ ἐξομολογούμενοι τὰς ἁμαρτίας αὐτῶν.

And they were baptized by him in Jordan, confessing their sins.