4:17 Ephraim - The children of Ephraim were numerous and potent, and here put for the whole ten tribes. Let him alone - He is obstinate, as such, throw him up.
4:12-19 The people consulted images, and not the Divine word. This would lead to disorder and sin. Thus men prepare scourges for themselves, and vice is spread through a people. Let not Judah come near the idolatrous worship of Israel. For Israel was devoted to idols, and must now be let alone. When sinners cast off the easy yoke of Christ, they go on in sin till the Lord saith, Let them alone. Then they receive no more warnings, feel no more convictions: Satan takes full possession of them, and they ripen for destruction. It is a sad and sore judgment for any man to be let alone in sin. Those who are not disturbed in their sin, will be destroyed for their sin. May we be kept from this awful state; for the wrath of God, like a strong tempest, will soon hurry impenitent sinners into ruin.