If we call this David’s Psalm of Pious Resolutions, we shall perhaps remember it all the more readily. After the song of praise (the 100th) a psalm of practice not only makes variety, but comes in most fittingly. We never praise the Lord better than when we do those things that are pleasing in his sight.
Verse 1. “I will sing of mercy and judgment: unto thee, O Lord, will I sing.” The manner of expression bespeaks a humble resolution; I cannot sing of merit, but I will sing of mercy. To sing of mercy must be a humble song, for mercy towards a miserable sinner is a melting word; and to sing of “judgment” also must be a humble song, for judgement in every sense is an awful word. David knew what the subject of his song should be, and, he says, “I will sing of mercy and judgment.” And he knew who should be the object of his song, therefore, he says, “To thee, O Lord, will I sing.” He knew who should be the singer and, therefore, he says, “I” will do it; and he knew what manner of expression was needed, therefore, he says, I will sing of mercy and judgment: to thee, O Lord, will I sing.”
Verse 1. “I will sing of mercy and judgment.” It has been said, “We are accustomed to write our mercies in the sand, and our calamities in the rock.” We should do just the reverse.
Verse 2. “I will behave myself wisely in a perfect way … I will walk within my house with a perfect heart.” It is easier for most men to walk within the church or even in the world, with a perfect heart, than in their own families. How many are as meek as lambs among others, when at home they are wasps or tigers.
Can he be a good Christian that spends all his religion abroad and leaves none for his nearest relations at home?
Verse 3. “I will set no wicked thing before mine eyes: I hate the work of them that turn aside …” Having mentioned “them that turn aside” to evil, in general, David then enters into some particular cases: but when he does so, he does not mention drunkards, adulterers, murderers, or blasphemers, but he mentions those whose sins were scandalous, but no less dangerous. He will have nothing to do:
(1). With spiteful malicious people, who are ill-natured, and who will bear a grudge a long time, and not care what mischief they do to those against whom they have their pique. Verse 4 – “A forward heart shall depart from me.”
(2). With slanderers, and those who take a pleasure in wounding their neighbour’s reputation secretly; verse 5 – “whoso privily slandereth his neighbour, him will I cut off.”
(3). With haughty, conceited, ambitious people. None do more mischief in a family, in a court, in a church, for “only by pride cometh contention.” Therefore – verse 5 – “Him that hath an high look and a proud heart will not I suffer.
(4). With false deceitful people, that scruple not to tell lies, or commit frauds; verse 7 – “He that worketh deceit shall not dwell within my house: he that telleth lies shall not tarry in my sight.”
Herein David was a man after God’s own heart; for a proud look and a lying tongue are things that God hates.
And so – this Psalm is full of stern exclusiveness and of noble intolerance; not against theological error – not against uncourtly manners – not against political insubordination; but against the proud heart – the high look – the secret slanderer – the deceitful worker – the teller of lies. These are the “outlaws” from King David’s court; these are the “rebels” and “heretics” whom he would not suffer to dwell in his house, or tarry in his sight.
O Lord, will I contend;
And of such rebels in my heart,
Grant me to make an end.”