Luke 3:15-18

Now the people were in a state of expectation, and all were wondering in their hearts about John, as to whether he was the Christ (the Messiah, the Anointed). John answered them all by saying, “As for me, I baptize you [only] with water; but One who is mightier [more powerful, more noble] than I is coming, and I am not fit to untie the strap of His sandals [even as His slave]. He will baptize you [who truly repent] with the Holy Spirit and [you who remain unrepentant] with fire. [Matt 3:11] His winnowing fork is in His hand to thoroughly clear His threshing floor, and to gather the wheat (believers) into His barn (kingdom); but He will burn up the chaff (the unrepentant) with unquenchable fire.” So with many other appeals and various admonitions John preached the good news (gospel) to the people.