Jeremiah 16:11

Then shalt thou say unto them
In answer to their questions; not in a general way, but by observing to them particular sins, and those gross ones, they had been guilty of: because your fathers have forsaken me, saith the Lord;
that is, his worship, as the Targum; they had quitted his service, and left attending on his word and ordinances; and therefore it was but just with him to forsake them, and give them up into the hands of their enemies: and have walked after other gods, and have served them, and have
worshipped them;
were guilty of gross idolatry, serving and worshipping the creature more than and besides the Creator; even idols of gold, and silver, and brass, and wood, and stone, which were no gods; for there is no other true God besides the Lord; and which they were well informed of, and therefore their sin was the greater to leave him and worship them; and which sin, because of the heinousness of it, is repeated: and have forsaken me, and have not kept my law;
they forsook his worship, as the Targum, and did not observe the law of the decalogue or ten commandments; especially the two first of them, which required the worship of the one true God, and forbid the worshipping of others; and which threatened the visiting such iniquities of fathers upon the children, to the third and fourth generation, of such that hated the Lord; and such were these persons, as follows.