O Jerusalem. — The prophet’s answer to the cry that comes from the city. In that “washing of the heart” which had seemed impossible before (Jeremiah 2:22), but is thought of now as “possible with God,” is the one hope of salvation. (Comp. Isaiah 1:16.)
Vain thoughts. — The Hebrew has a force which the English does not reproduce, thoughts of vanity, thoughts of aven, i.e., of the word which had been specially applied, as in Beth-aven for Beth-el (the “house of vanity” for the “house of God”) to the idols which Israel and Judah worshipped (Hosea 4:15; Hosea 10:5; Amos 5:5).