If they did not kill Paul before they did eat or drink any more, they wished that they might become a cherem, or anathema; as Jericho and the inhabitants thereof were, being devoted to utter ruin and destruction. Or, if they did not execute this their wicked design, they would yield themselves to be anathematized, or excommunicated, as those that had broken their pact or agreement.
Related Commentaries of Acts 23:12
Acts 23:12
12 And when it was day, certain of the Jews banded together, and bound themselves under a curse,a saying that they would neither eat nor drink till they had killed Paul.