Isidore of Seville
Catena Aurea · Matthäusevangelium 14
But when Herod’s birthday was kept, the daughter of Herodias danced before them, and pleased Herod. Whereupon he promised with an oath to give her whatsoever she would ask. And she, being before instructed of her mother, said, Give me here John Baptist’s head in a charger. And the king was sorry: nevertheless for the oath’s sake, and them which sat with him at meat, he commanded it to be given her. And he sent, and beheaded John in the prison. And his head was brought in a charger, and given to the damsel: and she brought it to her mother. And his disciples came, and took up the body, and buried it, and went and told Jesus.
(Lib. Syn. ii. 10.) In evil promises then break faith. That promise is impious which must be kept by crime; that oath is not to be observed by which we have unwittingly pledged ourselves to evil. It follows, And she being before instructed of her mother said, Give me here John Baptist’s head in a charger.