What iniquity. Reference to Pentateuch (Deuteronomy 32:4). App-92.
iniquity. Hebrew. 'aval. App-44.
fathers. Not merely recently, but of old (Jeremiah 2:7; Judges 2:10, &c).
vanity. the vanity. Put by Figure of speech Metonymy (of Ad-junct), for vain things: i.e. idols. Compare Jeremiah 10:3-10; Jeremiah 10:15; Jeremiah 14:22; Jeremiah 16:19; Jeremiah 16:20; Deuteronomy 32:21. Act 14:15. 1 Corinthians 8:4.
become vain? Compare 2 Kings 17:15. Idolaters always become like the gods they worship. Compare Psalms 115:8; Psalms 135:18.