It is not entirely clear what is meant with the Guilt of Samaria. In Hebrew, the word usually translated as sin or guilt sounds very similar to the name of the Canaanite goddess, Asherah. King Ahab had erected an Asherah image in Samaria (1 Kings 16:32–33; 2 Kings 13:6). Perhaps a wordplay is used to allude to the idolatry of Israel. Swearing an oath by the Lord or another god was an act of worship and a belief in the authority of the god so named.1
14 Those who swear by the Guilt of Samaria, and say, ‘As your god lives, O Dan,’ and, ‘As the Way of Beersheba lives,’ they shall fall, and never rise again.”