The statutes of the LORD are right, rejoicing the heart: the commandment of the LORD is pure, enlightening the eyes. The statutes of the Lord - פקודים pikkudim, from פקד pakad, he visited, cared, took notice of, appointed to a charge. The appointments, or charge delivered by God to man for his regard and observance.
Are right - ישרים yesharim, from ישר yashar, to make straight, smooth, right, upright, opposed to crookedness in mind or conduct; showing what the man should be, both within and without. This is Their character.
Rejoicing the heart - As they show a man what he is to observe and keep in charge, and how he is to please God, and the Divine help he is to receive from the visitations of God, they contribute greatly to the happiness of the upright - they rejoice the heart. This is Their use.
The commandment - מצוה mitsvah, from צוה tsavah, to command, give orders, ordain. What God has ordered man to do, or not to do. What he has commanded, and what he has prohibited.
Is pure - From ברה barah, to clear, cleanse, purify. All God's commandments lead to purity, enjoin purity, and point out that sacrificial offering by which cleansing and purification are acquired. This is Its character.
Enlightening the eyes - Showing men what they should do. and what they should avoid. It is by God's commandments that we see the exceeding sinfulness of sin, and the necessity of redemption, so that we may love the Lord with all our heart, and our neighbor as ourselves. For this is the end of the commandment, and thus to enlighten the eyes is Its use.