John the Baptist is arrested
Herod the tetrarch put John the Baptist in prison for speaking out against Herod’s actions.
A Dictionary of Christ and the Gospels: Aaron–Zion
ARREST (Jn 18:2–11 = Mt 26:47–56 = Mk 14:43–52 = Lk 22:47–53).—When Judas, withdrawing from the Supper, betook himself to the high priests and informed them that he was ready to implement his agreement (see Betrayal), their simplest way would have been to accompany him back to the upper room and there
Key passages
Mt 14:3–5

For Herod, after arresting John, bound him and put him in prison on account of Herodias, the wife of his brother Philip, because John had been saying to him, “It is not permitted for you to have her.” And although he wanted to kill him, he feared the crowd, because they looked upon him as …

Mk 6:17–20

For Herod himself had sent and arrested John and bound him in prison because of Herodias, the wife of Philip his brother, because he had married her. For John had been saying to Herod, “It is not permitted for you to have your brother’s wife.” So Herodias held a grudge against him and was …

Lk 3:19–20

But Herod the tetrarch, who had been reproved by him concerning Herodias, his brother’s wife, and concerning all the evil deeds that Herod had done, added this also to them all: he also locked up John in prison.

See also
Topics & Themes