1 Kings 1:50,51

Adonijah feared, &c. He fled to the altar for protection and safety, it being a privileged place; not, indeed, by the appointment of the law, but by the custom of all nations. And caught hold on the horns of the altar With a resolution, it seems, of not stirring therefrom till Solomon had given his oath, or solemn word, not to take away his life. And by thus doing Adonijah appears to have hindered the offering of sacrifices on the altar till such time as Solomon granted his pardon. Let King Solomon swear that he will not slay his servant He owns Solomon as his king, and himself as his servant and subject; and being sensible of his guilt, and of the jealousy which kings have of their competitors, could not be satisfied without Solomon's oath.