'Horns of the Altar' in the Bible

And Adonijah, fearing Solomon, arose and went and caught hold on the horns of the altar.

And it was told Solomon, how that Adonijah for fear of king Solomon hath caught handfast by the horns of the altar, saying, "Let king Solomon swear unto me this day, that he will not slay his servant with the sword."

Then tidings came to Joab - for Joab had turned after Adonijah, but not after Absalom - whereupon he fled unto the tabernacle of the LORD and caught handfast on the horns of the altar.