Jeremiah 9:7-9

7Therefore this is what the Lord Almighty says: “See, I will refine and test them, for what else can I do because of the sin of my people?

8Their tongue is a deadly arrow; it speaks deceitfully. With their mouths they all speak cordially to their neighbors, but in their hearts they set traps for them.

9Should I not punish them for this?” declares the Lord. “Should I not avenge myself on such a nation as this?”