They are vanity, and the work of errors: in the time of their visitation they shall perish.
The work of errors - deceptions; from a Hebrew root, to stutter; then meaning to mock.
In the time of their visitation they shall perish - when God shall punish the idol-worshippers (namely, by Cyrus), the idols themselves shall be destroyed (Rosenmuller) (Jeremiah 10:11).