The law (teaching) of truth was in his mouth. All his teaching rested on those truths which were enshrined in the Divine Law (Deuteronomy 31:10-13; Deuteronomy 33:10). Iniquity; unfair decision. Neither false doctrine nor perverse judgment was found in him (Deuteronomy 17:8-10; Deuteronomy 19:17).
Walked with me. Not only his teaching was true, but his life was pure and good; he was the friend of God, living as always in his presence, in peace and uprightness. So Enoch and Noah are said to have "walked with God" (Genesis 5:24; Genesis 6:9).
Did turn many away from iniquity. The faithful discharge of duties and the holy life and teaching of the good priest led many sinners to repentance and amendment.