The Lord shall smite Israel, because they obeyed Jeroboam's wicked command of worshipping the calves, and that willingly, Hosea 5:11. As a reed is shaken in the water; easily and variously, hither and thither, with every wind; so shall the kingdom and people of Israel be always in an unquiet and unsettled posture, tossed to and fro by foreign invasions and civil wars, by opposite kings and factions, and by the dissensions of the people. See 2 Kings 17:18. Beyond the river, to wit, Euphrates, oft so called by way of eminency, as Genesis 15:18, Genesis 31:21 1 Kings 4:21,24. This was accomplished in part, 2 Kings 15:29, and more fully 2 Kings 17:6. Because they have made their groves, for the worship of their idols, Exodus 34:13 Deuteronomy 16:21. God having before condemned the making and worshipping of the calves, by which they designed or pretended to worship the true God; he now takes notice that they were not contented with the calves, but (as it is the nature of idolatry, and all sin, to proceed from evil to worse) were many of them fallen into another and a worse kind of idolatry, even their worship of the heathenish Baals, which they commonly exercised in groves. See Poole on "1 Kings 18:19".
Related Commentaries of 1 Kings 14:15
1 Kings 14:15
15 For the LORD shall smite Israel, as a reed is shaken in the water, and he shall root up Israel out of this good land, which he gave to their fathers, and shall scatter them beyond the river, because they have made their groves, provoking the LORD to anger.