The way of the just is uprightness: thou, most upright, dost weigh the path of the just.
The way of the just (is) uprightness - rather, is direct; i:e., is directed by God to a prosperous issue, however many be their afflictions in the meantime (as in the case of the Jewish exiles). The context requires this sense (Psalms 34:19; Proverbs 3:6; Proverbs 11:5) - literally, 'rightnesses.' The prophet is not praising the just, but is showing that God gives a prosperous issue to their course, however rugged it may seem for a time (Calvin, Maurer). Thus "The way" means God's dealings with the righteous (Psalms 37:23).
Thou, most upright - (Deuteronomy 32:4.)
Dost weigh the path of the just (1 Samuel 2:3; Proverbs 5:21) - thou dost exactly level (Maurer), removing all obstacles (Isaiah 40:3-4). Junius explains, 'thou makest all things most exactly to succeed in the path of the just, controlling each of the two scales, adversity and prosperity, more nicely than any goldsmith.