Psalms 1:2 - Matthew Poole's English Annotations on the Holy Bible

In the law, i.e. in the study and practice of it, as appears from the context. The law of God may be here understood of the whole doctrine delivered by God to the church, consisting of doctrines, precepts, promises, and threatening, &c.; as it is taken Psalms 37:1, Psalms 58:1 Isaiah 51:7 1 Thessalonians 10:34; or more particularly of the preceptive part of it, which is commonly so called; and so this is noted as the peculiar character of a good man, that he delighteth himself not only in the promises, which a bad man may do, Matthew 13:20, but even in the commands of God, Psalms 112:1, Psalms 119:47 127 143 1 John 5:3, which are unwelcome and burdensome to a wicked man. The word meditate implies a deep, and serious, and affectionate thoughtfulness about it: see Psalms 19:14, Psalms 49:3 Proverbs 24:2 Isaiah 33:18. Day and night; not seldom and slightly, as hypocrites do; but diligently, frequently, constantly, and upon all occasions.