Psalms 19:9

9.The fear of Jehovah is clean. By the fear of God we are here to understand the way in which God is to be served; and therefore it is taken in an active sense for the doctrine which prescribes to us the manner in which we ought to fear God. The way in which men generally manifest their fear of God, is by inventing false religions and a vitiated worship; in doing which they only so much the more provoke his wrath. David, therefore, here indirectly condemns these corrupt inventions, about which men torment themselves in vain, (456) and which often sanction impurity; and in opposition to them he justly affirms, that in the keeping of the law there is an exemption from every thing which defiles. He adds, that it endures for ever; as if he had said, This is the treasure of everlasting happiness. We see how mankind, without well thinking what they are doing, pursue, with impetuous and ardent affections, the transitory things of this world; but, in thus catching at the empty shadow of a happy life, they lose true happiness itself. In the second clause, by calling the commandments of God truth, David shows that whatever men undertake to do at the mere suggestion of their own minds, without having a regard to the law of God as a rule, is error and falsehood. And, indeed, he could not have more effectually stirred us up to love, and zealously to live according to the law, than by giving us this warning, that all those who order their life, without having any respect to the law of God, deceive themselves, and follow after mere delusions. Those who explain the word judgments, as referring only to the commandments of the second table, are, in my opinion, mistaken: for David’s purpose was to commend, under a variety of expressions, the advantages which the faithful receive from the law of God. When he says, They are justified together, the meaning is, They are all righteous from the greatest to the least, without a single exception. By this commendation he distinguishes the law of God from all the doctrines of men, for no blemish or fault can be found in it, but it is in all points absolutely perfect.