The children of Ephraim were numerous and potent among the ten tribes, a principal part of them, and out of which tribe the first idolater and usurper did arise, 1Ki_11:26; and therefore the whole body of the ten tribes, and the rulers among them, are here particularly pointed at.
Is joined to idols; associated as friends to friends, or joined as lovers are joined to lovers; married to idols, and will not be taken off.
Let him alone; he is indeed obstinately bent on his old courses, and as such throw him up; he will not return; let him wander, but let it be alone, O Judah, be not his companion, his friend, go not with him.