Proverbs 6:23 (ESV) … “For the commandment is a lamp and the teaching a light, and the reproofs of discipline are the way of life…”
The law of God is a lamp or candle to see to work by and to walk by; it enlightens the eyes and directs the feet, and makes working more pleasant, and walking more comfortable; and indeed without it a man knows not rightly what to do or where he should walk, or where he is walking; Psalm 119:105 “Your word is a lamp to my feet and a light to my path.”
And the law is light; it makes things clear and manifest, what is right and what is wrong; it enlightens the eyes of the understanding, whereby persons come to see both their sin and their duty; and it directs them to avoid the one and do the other; Psalm 19:8 (ESV) “the precepts of the Lord are right, rejoicing the heart; the commandment of the Lord is pure, enlightening the eyes…”
And reproofs of instruction are the way of life; kind reproofs given by parents agreeable to the word of God, which instruct what should be shunned and what should be performed, when attended to, put men in the way of an honorable and useful life; and are the means of preserving them from a scandalous and useless one.[1]
[1] Gill, J. (1810). An Exposition of the Old Testament (Vol. 4, p. 368). London: Mathews and Leigh.