The word iniquity in the KJV (Hebrew: Avon) means to commit wrong intentionally. When you know something is wrong but do it anyway, giving in to your desires. It is something twisted or distorted, the purposeful breaking of God’s moral law and a turning from the perfect will of God even though you know its wrong. Psalms 119:11 Thy word have I hid in mine heart, that I might not sin against thee