Luke 1:5

During the time when Herod was king. Herod the Great (see note on Matthew 2:1). A priest named Zechariah. Not a "chief priest," one of the lower ranks. Order of Abijah. All the priests were grouped in twenty-four orders. The "Order of Abijah" was the eighth (1 Chronicles 24:10). Each Order took charge of the temple worship in sequence, for a week at a time beginning on the Sabbath. The "heads" of these twenty-four Orders are the "chief priests." His wife's name was Elizabeth. She is also from a priestly family, so John the Baptist is of "priestly descent" on both sides of his family.