C. F. Keil and Franz Delitzsch on Proverbs 21:3

Pro 21:3 3 To practice justice and right    Hath with Jahve the pre-eminence above sacrifice.

We have already (vol. i. p. 42) shown how greatly this depreciation of the works of the ceremonial cultus, as compared with the duties of moral obedience, is in the spirit of the Chokma; cf. also at Pro 15:8. Prophecy also gives its testimony, e.g., Hos 6:7, according to which also here (cf. Pro 20:8 with Isa 9:8) the practising of צדקה וּמשׁפּט (sequence of words as at Gen 18:19; Psa 33:5, elsewhere צדק ומשׁפט, and yet more commonly משׁפט וצדקה) does not denote legal rigour, but the practising of the justum et aequum, or much rather the aequum et bonum, thus in its foundation conduct proceeding from the principle of love. The inf. עשׂה (like קנה, Pro 16:16) occurs three times (here and at Gen 50:20; Psa 101:3); once עשׂו is written (Gen 31:18), as also in the infin. absol. the form עשׂה mro and עשׂו interchange (vid., Norzi at Jer 22:4); once עשׂהוּ for עשׂותו (Exo 18:18) occurs in the status conjunctus.