The king’s strength - The word king here undoubtedly refers to God as a king, Psalms 99:1. The word rendered “strength,” means power, force; and the reference here is to what constitutes the main strength or power of his character and government. It is rendered in the Septuagint, τιμή timē - “honor.” So in the Latin Vulgate - ”honor.” DeWette renders it, “The praise of the king who loves judgment.” So Rosenmuller, “Let them praise the strength - the power - of the king who loves judgment.” But perhaps our common version best expresses the sense, that whatever there is in the character of the “king,” that is God, which constitutes strength, or gives power to his administration, is favorable to justice, or will be exerted in the cause of right. God’s essential character; all the acts of his power; all the demonstrations of his authority, will be in favor of justice, and may be relied on as sustaining the righteous cause. It is not the “mere” exertion of power - it is power that is always exercised in favor of right; and this lays the foundation of praise. We could not praise a being of “mere” power, or one who was merely “almighty,” without respect to his moral character. It is only when the character is such that power will be exerted in favor of that which is right and just that it becomes the proper subject of praise.
Loveth judgment - Is always on the side of justice and right. He so loves justice that his power will be put forth only in behalf of that which is right. God shows this by his law, and by all the acts of his administration.
Thou dost establish equity - That which is equal and just; alike by thy law, and by thine interpositions. All that thou doest, and all that thou dost appoint, is in favor of that which is equal and just.
Thou executest judgment and righteousness in Jacob - That which is just; that which ought to be done. Thou doest this among thy people; thou doest it in their relation to the surrounding nations. All the acts of thy administration tend to the establishment of that which is right.