In the fifth verse, the prophet teaches that a happy life depends on a good conscience, and that, therefore, it is not wonderful, if the ungodly suddenly fall from the happiness of which they fancied themselves in possession. And there is implied in the words a kind of concession; the prophet tacitly acknowledges that the ungodly please and enjoy themselves, and triumph during the reign of moral disorder in the world; just as robbers revel in the woods and caves, when beyond the reach of justice. But he assures us, that things will not always remain in their present state of confusion, and that when they shall have been reduced to proper order, these ungodly persons shall be entirely deprived of their pleasures, and feel that they were infatuated when they thought themselves happy. We now see how the Psalmist pronounces the ungodly to be miserable, because happiness is the inward blessing of a good conscience. He does not deny, that before they are driven to judgment, all things succeed well with them; but he denies that they are happy unless they have substantial and steadfast integrity of character to sustain them: for the true integrity of the righteous manifests itself when it comes at length to be tried. It is indeed true, that the Lord daily executes judgment, by making a distinction between the righteous and the wicked, but because this is done only partially in this life, we must look higher if we desire to behold the assembly of the righteous, of which mention is here made.
Even in this world the prosperity of the ungodly begins to pass away as often as God manifests the tokens of his judgment; (for then, being awakened out of sleep, they are constrained to acknowledge, whether they will or no, that they have no part with the assembly of the righteous;) but because this is not accomplished always, nor with respect to all men, in the present state, we must patiently wait for the day of final revelation, in which Christ will separate the sheep from the goats. At the same time, we must maintain it as a general truth, that the ungodly are devoted to misery; for their own consciences condemn them for their wickedness; and, as often as they are summoned to give an account of their life, their sleep is broken, and they perceive that they were merely dreaming when they imagined themselves to be happy, without looking inward to the true state of their hearts.
Moreover, as things appear to be here driven about at the mercy of chance, and as it is not easy for us, in the midst of the prevailing confusion, to acknowledge the truth of what the Psalmist had said, he therefore presents to our consideration the grand principle, that God is the Judge of the world. Granting this, it follows that it cannot but be well with the upright and the just, while, on the other hand, the most terrible destruction must impend over the ungodly. According to all outward appearance, the servants of God may derive no advantage from their uprightness; but as it is the peculiar office of God to defend them and take care of their safety, they must be happy under his protection. And from this we may also conclude that, as he is the certain avenger of wickedness, although, for a time, he may seem to take no notice of the ungodly, yet at length he will visit them with destruction. Instead, therefore, of allowing ourselves to be deceived with their imaginary felicity, let us, in circumstances of distress, have ever before our eyes the providence of God, to whom it belongs to settle the affairs of the world, and to bring order out of confusion.