Adam Clarke on Micah 6:2

Hear ye, O mountains - Micah, as God's advocate, summons this people into judgment, and makes an appeal to inanimate creation against them. He had spoken to the priests, to the princes, to the people. He had done every thing that was necessary to make them wise, and holy, and happy; they had uniformly disobeyed, and were ever ungrateful. It was not consistent with either the justice or mercy of God to permit them to go on without reprehension and punishment. He now calls them into judgment; and such was the nature of their crimes that, to heighten the effect, and show what reason he had to punish such a people, he appeals to inanimate creation. Their ingratitude and rebellion are sufficient to make the mountains, the hills, and the strong foundations of the earth to hear, tremble, and give judgment against them. This, then, is the Lord's controversy with his people, and thus he will plead with Israel.