Matthew 8:12, Children/Sons of the kingdom. This is a Hebraism or biblical metaphor for the Jewish people. They are the ones who were first presented with the gospel message, but most of them rejected it. The sons of the kingdom will be cast into outer darkness because they didn’t accept Yeshua the Messiah, who is the light of the world (John 1:9; 8:12). It’s rather ironic to be cast into darkness for not accepting the light. Unrepentant sinners prefer darkness over the light because their deeds are evil (John 3:19), so in the end they get what they really wanted.
Outer darkness. (Also 22:13; 25:30.) Ancient banquets were held at night in brilliantly lit rooms, and anyone excluded from the feast was cast outside into outer darkness. In his teachings, Yeshua’s uses this term as a metaphor for judgment in reference to those who will be excluded from his kingdom. In the oriental mind, in the days before street lights, it was a dreadful thing to be found outside, late at night no lamp or simply a small clay lamp of that day that put out a tiny, dim flame (Manners and Customs, pp. 62–63). This speaks of the fear that those whom Yeshua will reject will experience.