Jeremiah 18:15

“Because my people hath forgotten me, etc.] Or, “that they have forgotten me”f386; this is the horrible thing they have done, which was unheard of among the Gentiles, who were always tenacious of their gods, and the worship of them; and that foolish and unwise thing, which was like leaving pure flowing streams of water for dirty puddles. This is to be understood of their forsaking the worship of God, as the Targum interprets it, and following after idols: they have burnt incense to vanity; to idols, which are vain empty things, and which cannot give their worshippers what they expect from them: or, “in vain they burn incense”f387; even to the true God, while they also sacrificed unto idols;…”

“Because--rather, "And yet"; in defiance of the natural order of things. forgotten me-- (Jer 2:32). This implies a previous knowledge of God, whereas He was unknown to the Gentiles; the Jews' forgetting of God, therefore, arose from determined perversity. they have caused . . . to stumble--namely the false prophets and idolatrous priests have. ancient paths-- (Jer 6:16): the paths which their pious ancestors trod. Not antiquity indiscriminately, but the example of the fathers who trod the right way, is here commended. them--the Jews. not cast up--not duly prepared: referring to the raised center of the road. CALVIN translates, "not trodden." They had no precedent of former saints to induce…”

“Because - “For.” Jeremiah returns to, and continues the words of, Jeremiah 18:13. Vanity - A word meaning “falsehood,” which signifies that the worship of idols is not merely useless but injurious. They have caused them to stumble - Judah’s prophets and priests were they who made her to err Jeremiah 5:31. The idols were of themselves powerless for good or evil. In their ways ... - Or, “in their ways, the everlasting paths, to walk in byways, in a road not cast up. The paths of eternity” carry back the mind not to the immediate but to the distant past, and suggest the good old ways in which the patriarchs used to walk. The “road cast up” means one raised sufficiently to keep it out of the…”

“Vanity - Idols. Ancient paths - The ways wherein Noah, Abraham, Isaac, and Jacob, and all the ancient patriarchs walked. To walk - In a way not cast up, not fit for God's people to walk in. Jeremiah 18:16”

“my people: Jer 2:13, Jer 2:19, Jer 2:32, Jer 3:21, Jer 13:25, Jer 17:13 burned: Jer 10:15, Jer 16:19, Jer 44:15-19, Jer 44:25; Isa 41:29, Isa 65:7; Hos 2:13, Hos 11:2 caused: Isa 3:12, Isa 9:16; Mal 2:8; Mat 15:6; Rom 14:21 the ancient: Jer 6:16 to walk: Jer 19:5; Isa 57:14 Jeremiah 18:16”