What does Amos 7:8 mean?

The Lord asked me, 'Amos, what do you see?' I said, 'A plumb line.' Then the Lord said, 'I'm setting a plumb line among my people Israel. I won't ignore what they're doing anymore.' Amos 7:8 - Modern Text Bible

(God is saying he's measuring Israel's faithfulness, and they've failed the test. He's not going to overlook their wrongs any longer.)