Psalms 19:8

The statutes of the Lord [are] right
The word of God may be called "statutes", or "visitations" ^F4 because that God will visit, in a way of resentment, such persons as despise its authority, do not act according to it, or add unto it, or detract from it; or the word may be rendered "commissions" ^F5, things committed to trust, as the Scriptures were to the Jews, ( Romans 3:1 Romans 3:2 ) ; and as the Gospel is committed to the trust of the ministers of it, who faithfully dispense it, ( 2 Corinthians 5:19 ) ( 1 Timothy 1:11 ) . Now these may be said to be right, as the word of the Lord is, ( Psalms 33:4 ) ; since they set men right in their principles, and direct them to right practices; they are the means of making them upright in heart, and in conversation: the doctrines of the word of God have nothing crooked, froward, and perverse in them; are without sophism, and the hidden things of dishonesty; they are all in righteousness, and plain and easy in everything respecting salvation, to those who have a spiritual knowledge and understanding of them, ( Proverbs 8:8 Proverbs 8:9 ) ; they lead into right and straight paths of truth and holiness, in which wayfaring men, though fools, shall not err; and particularly the Gospel directs to the right way of salvation and eternal life by Jesus Christ; the effect of which is

rejoicing the heart.
This cannot be understood of the law, which is a voice of terror, pronounces guilty, curses and condemns, is the killing letter, and works wrath; but of the Gospel part of the word, which is a joyful sound; publishes good tidings of good things; and, when applied by the Spirit of God, is found to have this effect, see ( Jeremiah 15:16 ) ;

the commandment of the Lord [is] pure;
not only the Scriptures in general may bear this name, because they deliver out the commands of God to men, as those of a moral and ceremonial kind to the Jews under the former dispensation; so the ordinances of Christ, which are his commands under the Gospel dispensation; yea, the Gospel itself may be so called, though, strictly speaking, it has no command in it; because, according to the commandment of the everlasting God, it is made known to all nations for the obedience of faith, ( Romans 16:25 Romans 16:26 ) ; besides, the commandment is no other than the word or doctrine, see ( 1 John 2:7 ) ; and as every commandment of the Lord, of what kind soever it is, is pure and holy, so is every word of God, ( Proverbs 30:5 ) ; being without any mixture of men's inventions, or the dross of corrupt doctrine, sincere, unadulterated, clear of all chaff and impurity, consistent, uniform, and all of a piece, and which tends to promote purity of heart, life, and conversation;

enlightening the eyes:
that is, of the understanding, so as for a man to see his lost state and condition by nature; to see the glory, fulness, and grace of Christ; to behold wondrous things in the doctrine of the Gospel, and to observe the way of duty in which he should walk: this is the eyesalve in ( Revelation 3:18 ) ; and so the Jewish doctors ^F6 explaining this text call the law, using the same word as there.