Church Fathers Commentary Luke 3:18-20

"With many other exhortations therefore preached he good tidings unto the people; but Herod the tetrarch, being reproved by him for Herodias his brother`s wife, and for all the evil things which Herod had done, added this also to them all, that he shut up John in prison." — Luke 3:18-20 (ASV)

Origen of Alexandria: After John announced the coming of Christ, he preached the baptism of the Holy Spirit and the other things the Gospel history has handed down to us. But besides these, he is said to have announced other things in the following words: And many other things in his exhortation preached he to the people.

Theophylact of Ohrid: For his exhortation was the telling of good things, and therefore is rightly called the Gospel.

Origen of Alexandria: Just as the Gospel according to John relates that Christ spoke many other things, so also in this place we must understand that Luke says the same of John the Baptist, since some things announced by John were too great to be entrusted to writing. But we marvel at John, because among those who are born of women there was not a greater than he; for by his good deeds he had been exalted to such a high reputation for virtue that many supposed he was the Christ. But what is much more marvelous, he did not fear Herod or dread death, as it follows: But Herod the tetrarch being reproved by him.

Eusebius of Caesarea: He is called the tetrarch to distinguish him from the other Herod, in whose reign Christ was born, who was a king; this Herod, however, was a tetrarch. His wife was the daughter of Aretas, king of Arabia, but he had sacrilegiously married his brother Philip’s wife, even though she had a child by his brother. For only those whose brothers died without issue were allowed to do this.

For this reason, the Baptist had censured Herod. At first, Herod heard him attentively, knowing that his words were weighty and full of consolation. But the desire of Herodias compelled him to despise John's words, and he then threw him into prison. And so it follows: And he added this above all, that he shut up John in prison.

The Venerable Bede: But John was not imprisoned at that time. According to John’s Gospel, this did not happen until after our Lord had performed some miracles and His baptism had become widely known. According to Luke, however, he had been seized beforehand due to the intensified malice of Herod.

For when Herod saw so many flocking to John’s preaching—with soldiers believing, tax collectors repenting, and whole multitudes receiving baptism—he, on the contrary, not only despised John but also imprisoned and killed him.

Glossa Ordinaria: For before Luke relates any of the acts of Jesus, he says that John was imprisoned by Herod. He does this to show that he, Luke, was specifically going to describe those acts of our Lord that were performed after the year John was imprisoned or put to death.