There is not a just man upon earth, that doeth good, and sinneth not - יחטא לא lo yechta, that may not sin. There is not a man upon earth, however just he may be, and habituated to do good, but is peccable - liable to commit sin; and therefore should continually watch and pray, and depend upon the Lord. But the text does not say, the just man does commit sin, but simply that he may sin; and so our translators have rendered it in 1 Samuel 2:25, twice in 1 Kings 8:31, 1 Kings 8:46, and 2 Chronicles 6:36; and the reader is requested to consult the note on 1 Kings 8:46, where the proper construction of this word may be found, and the doctrine in question is fully considered.
The connection of this verse with Ecclesiastes 7:18-19 becomes clearer if it is borne in mind that the fear of God, wisdom, and justice, are merely different sides of one and the same character, the formation of which is the aim of all the precepts in this chapter. The words “just” Ecclesiastes 7:15, Ecclesiastes 7:20 and “righteous” Ecclesiastes 7:16 are exactly the same in Hebrew.