Psalms 119:104

But what mean the words, "Through Thy commandments I get understanding"? (ver. 104). For the expressions, I have understood Thy commandments: and, "I get understanding through Thy commandments;" are different. Something else then he signifieth that he hath understood from the commandments of God: that is, as far as I can see, he saith, that by obeying God's commandments he hath arrived at the comprehension of those things which he had longed to know. ...These then are the words of the spiritual members of Christ, "Through Thy commandments I get understanding." For the body of Christ rightly saith these words in those, to whom, while they keep the commandments, a richer knowledge of wisdom is given on account of this very keeping of the commandments. "Therefore," he addeth, "I hate all evil ways." For it is needful that the love of righteousness should hate all iniquity: that love, which is so much the stronger, in proportion as the sweetness of a higher wisdom doth inspire it, a wisdom given unto him who obeyeth God, and getteth understanding from His commandments.

Avoidance of sinful courses is both the effect and means of increasing in divine knowledge (compare Ps 19:10).

"Through thy precepts I get understanding." God's direction is our instruction. Obedience to the divine will begets wisdom of mind and action. As God's way is always best, those who follow it are sure to be justified by the result. If the Lawgiver were foolish his law would be the same, and obedience to such a law would involve us in a thousand mistakes; but as the reverse is the case, we may count ourselves happy to have such a wise, prudent, and beneficial law to be the rule of our lives.

"Through thy precepts I get understanding." God's direction is our instruction. Obedience to the divine will begets wisdom of mind and action. As God's way is always best, those who follow it are sure to be justified by the result. If the Lawgiver were foolish his law would be the same, and obedience to such a law would involve us in a thousand mistakes; but as the reverse is the case, we may count ourselves happy to have such a wise, prudent, and beneficial law to be the rule of our lives. We are wise if we obey and we grow wise by obeying! "Therefore I hate every false way." Because he had understanding, and because of the divine precepts, he detested sin and falsehood. Every sin is a falsehood; we commit sin because we believe a lie, and in the end the flattering evil turns a liar to us and we find ourselves betrayed. True hearts are not indifferent about falsehood, they grow warm in indignation: as they love the truth, so they hate the lie. Saints have a universal horror of all that is untrue, they tolerate no falsehood or folly, they set their faces against all error of doctrine or wickedness of life. He who is a lover of one sin is in league with the whole army of sins; we must have neither truce nor parley with even one of these Amalekites, for the Lord hath war with them from generation to generation, and so must we. It is well to be a good hater. And what is that? A hater of no living being, but a hater of "every false way." The way of self will, of self righteousness, of worldliness, of pride, of unbelief, of hypocrisy,—these are all false ways, and therefore not only to be shunned, but to be abhorred. This final verse of the strophe marks a great advance in character, and shows that the man of God is growing stronger, bolder, and happier than aforetime.

Through thy precepts I get understanding - Spiritual knowledge increases while we tread in the path of obedience. Obedience is the grand means of growth and instruction. Obedience trades with the talent of grace, and thus grace becomes multiplied.