John answered them all, "I indeed baptize you with water, but he comes who is mightier than I, the latchet of whose sandals I am not worthy to loosen. He will baptize you in the Holy Spirit and fire,

 Here we have Luke's genealogy of Jesus. The Jews were interested in genealogies. Genealogies, especially of the priests, who had to prove unbroken descent from Aaron, were kept amongst the public records. In the time of Ezra and Nehemiah we read of priests who lost their office because they could not produce their genealogy ( Ezra 2:61-63; Nehemiah 7:63-65). 