Glossa Ordinaria
Catena Aurea · Lukasevangelium 3
And many other things in his exhortation preached he unto the people. But Herod the tetrarch, being reproved by him for Herodias his brother Philip’s wife, and for all the evils which Herod had done, Added yet this above all, that he shut up John in prison.
(ordin.) For before that Luke relates any of the acts of Jesus, he says that John was taken by Herod, to shew that he alone was in an especial manner going to describe those of our Lord’s acts, which were performed since the year in which John was taken or put to death.