Mark 6:18

6:18 For John had repeatedly told Herod, “It is not lawful for you to have your brother’s wife.”

Mark 10:2

10:2 Then some Pharisees came, and to test him they asked, “Is it lawful for a man to divorce his wife?”

Mark 12:23

12:23 In the resurrection, when they rise again, whose wife will she be? For all seven had married her.”