לְדָוִ֨ד ׀ שָׁפְטֵ֤נִי יְהוָ֗ה כִּֽי־אֲ֭נִי בְּתֻמִּ֣י הָלַ֑כְתִּי וּבַיהוָ֥ה בָּ֝טַ֗חְתִּי לֹ֣א אֶמְעָֽד׃
屬大衛的。永恆者啊，求你為我判斷，因為我一向行事純全；我倚靠永恆者，必不動搖。
Radak
He that walketh perfectly: – If תמים (perfect) is an adjective, his meaning is, One who walks in a perfect way, as, “He that walketh in a perfect way, he shall minister unto me” (ibid. 101:6); while if it is a noun, (it is used) as (in the passage) “if in truth and perfectness (בתמים)” (Judges 9:16). He means: He who walks in perfectness (integrity), as, “But as for me I will walk in mine integrity (בתמי)” (Ps. 26:11). But in either case the meaning is the same. The perfect is he who occupies himself in the affairs of this world in the way of perfectness (integrity), who does not engage his deepest purpose in (the prosecution of) worldly schemes.