Jeremiah 6:26-27

26O daughter of my people [says Jeremiah], Clothe yourself in sackcloth and wallow in ashes; Mourn [aloud] as for an only son, A most bitter cry [of sorrow and regret], For suddenly the destroyer will come upon us [on both prophet and people].

27“I [the Lord] have set you as an assayer [O Jeremiah] and as a tester [of the ore] of My people, That you may know and analyze their acts.”