O how have I loved thy law! Not contented with a simple affirmation, the prophet exclaims, by way of interrogation, that he was inflamed with incredible love to the law of God; and, in proof of this, he adds, that he was continually engaged in meditating upon it. If any person boasts that he loves the Divine Law, and yet neglects the study of it, and applies his mind to other things, he betrays the grossest hypocrisy; for the love of the law, and especially such an ardent love of it as the prophet here expresses, always produces continual meditation upon it. And, assuredly, unless God's law inflame and ravish our hearts with the love of it, many allurements will quickly steal upon us, and lead us away to vanity. The prophet, then, here commends such a love of the law, as, possessing all our senses, effectually excludes all the deceits and corruption's to which we are otherwise too much inclined.

O how love I thy law! - This commences a new division of the Psalm, indicated by the Hebrew letter Mem (מ m, "m"). The expression here, "O how love I thy law," implies intense love - as if a man were astonished at the fervour of his own emotion. His love was so ardent that it was amazing and wonderful to himself - perhaps wonderful that he, a sinner, should love the law of God at all; wonderful that he should ever have been brought so to love a law which condemned himself. Any man who reflects on what his feelings are by nature in regard to religion, will be filled with wonder that he loves it at all; all who are truly religious ought to be so filled with love to it, that it will be difficult for them to find words to express the intensity of their affection.
It is my meditation all the day - See the notes at Psalm 1:2.

O how love I thy law - This is one of the strongest marks of a gracious and pious heart, cast in the mould of obedience. Such love the precepts of Christ: in his commandments they delight; and this delight is shown by their making them frequent subjects of their meditation.

MEM. O how love I thy law! it [is] my meditation (a) all the day.
(a) He shows that we cannot love God's word unless we exercise ourselves in it and practise it.

MEM.--The Thirteenth Part.
MEM. O how love I thy law!.... The whole word of God, the preceptive part of it; the commands of the moral law, which are holy, just, and good, and to be loved: but they are not loved by carnal men, whose minds are enmity to them, and therefore are not and cannot be subject to them, but despise and reject them; but to a good man, on whose heart they are written, they are delightful, and loved to admiration: though this is wholly owing to the grace of God; and marvellous it is that men so sadly depraved by sin should love the holy law of God; yet so it is, and David could appeal to God for the truth of it. So the ordinances of the Gospel, the commands of Jesus Christ, are not grievous to saints, but loved, valued, and esteemed by them; likewise the doctrinal part of the word, the truths of the Gospel, which may be more especially meant by the "thorah", or doctrine, here; which those who have had an experience of greatly love and justly value, because of the intrinsic worth of them, being comparable to gold, silver, and precious stones; and for the profit and benefit of them to their souls, they being wholesome words, soul nourishing doctrines, and so more to them than their necessary food; and for the pleasure they have in them, these being sweeter to them than the honey or honeycomb: particularly the exceeding great and precious promises of the word, which are more to be rejoiced at than a great spoil; and even the whole Gospel part of the word, that containing the doctrines of peace, pardon, righteousness, salvation, and eternal life through Christ; yea, the whole Scripture, which is both profitable and pleasant to read in, and hear explained;
it is my meditation all the day; not only in the night, when at leisure, and free from the incumbrance of business; but in the day, and while engaged in the affairs of life, yea, all the day long; see Psalm 1:2. Or, "it is my discourse" (c); what he talked of, as well as what he thought on. Good men cannot forbear speaking of this or the other passage of Scripture, which has been of use unto them: and this is a proof of affection for the word; for what men love, persons or things, they often think of, and frequently talk of; see Deuteronomy 6:6.
(c) "de qua meus sermo est", Tigurine version, Vatablus, Piscator; "vel colloquium meum", Cocceius; so Michaelis.

What we love, we love to think of. All true wisdom is from God. A good man carries his Bible with him, if not in his hands, yet in his head and in his heart. By meditation on God's testimonies we understand more than our teachers, when we understand our own hearts. The written word is a more sure guide to heaven, than all the fathers, the teachers, and ancients of the church. We cannot, with any comfort or boldness, attend God in holy duties, while under guilt, or in any by-way. It was Divine grace in his heart, that enabled the psalmist to receive these instructions. The soul has its tastes as well as the body. Our relish for the word of God will be greatest, when that for the world and the flesh is least. The way of sin is a wrong way; and the more understanding we get by the precepts of God, the more rooted will be our hatred of sin; and the more ready we are in the Scriptures, the better furnished we are with answers to temptation.

MEM. (Psalm 119:97-104).
This characteristic love for God's law (compare Psalm 1:2) ensures increase.

The eightfold Mem. The poet praises the practical wisdom which the word of God, on this very account so sweet to him, teaches. God's precious law, with which he unceasingly occupies himself, makes him superior in wisdom (Deuteronomy 4:6), intelligence, and judgment to his enemies, his teachers, and the aged (Job 12:20). There were therefore at that time teachers and elders (πρεσβύτεροι), who (like the Hellenizing Sadducees) were not far from apostasy in their laxness, and hostilely persecuted the young and strenuous zealot for God's law. The construction of Psalm 119:98 is like Joel 1:20; Isaiah 59:12, and frequently. היא refers to the commandments in their unity: he has taken possession of them for ever (cf. Psalm 119:111). The Mishna (Aboth iv. 1) erroneously interprets: from all my teachers do I acquire understanding. All three מן in Psalm 119:98-100 signify prae (lxx ὑπὲρ). In כּלאתי, Psalm 119:101, from the mode of writing we see the verb Lamed Aleph passing over into the verb Lamed He. הורתני is, as in Proverbs 4:11 (cf. Exodus 4:15), a defective mode of writing for הוריתני. נמלצוּ, Psalm 119:103, is not equivalent to נמרצוּ, Job 6:25 (vid., Job, at Job 6:25; Job 16:2-5), but signifies, in consequence of the dative of the object לחכּי, that which easily enters, or that which tastes good (lxx ὡς gluke'a); therefore surely from מלץ = מלט, to be smooth: how smooth, entering easily (Proverbs 23:31), are Thy words (promises) to my palate or taste! The collective singular אמרתך is construed with a plural of the predicate (cf. Exodus 1:10). He has no taste for the God-estranged present, but all the stronger taste for God's promised future. From God's laws he acquires the capacity for proving the spirits, therefore he hates every path of falsehood (= Psalm 119:128), i.e., all the heterodox tendencies which agree with the spirit of the age.