From Matthew Henry’s Commentary on the Book of Leviticus, Chapter 19, verse 3:
“That children be obedient to their parents: “You shall fear every man his mother and his father, v. 3. 1. The fear here required is the same with the honour commanded by the fifth commandment; see Mal. i. 6. It includes inward reverence and esteem, outward expressions of respect, obedience to the lawful commands of parents, care and endeavour to please them and make them easy, and to avoid every thing that may offend and grieve them, and incur their displeasure. The Jewish doctors ask, “What is this fear that is owing to a father?” And they answer, “It is not to stand in his way nor to sit in his place, not to contradict what he says nor to carp at it, not to call him by his name, either living or dead, but ‘My Father,’ or ‘Sir;’ it is to provide for him if he be poor, and the like.” 2. Children, when they grow up to be men, must not think themselves discharged from this duty: every man, though he be a wise man, and a great man, yet must reverence his parents, because they are his parents. 3. The mother is put first, which is not usual, to show that the duty is equally owing to both; if the mother survive the father, still she must be reverenced and obeyed. 4. It is added, and keep my sabbaths. If God provides by his law for the preserving of the honour of parents, parents must use their authority over their children for the preserving of the honour of God, particularly the honour of his sabbaths, the custody of which is very much committed to parents by the fourth commandment, Thou, and thy son, and thy daughter. The ruin of young people has often been observed to begin in the contempt of their parents and the profanation of the sabbath day. Fitly therefore are these two precepts here put together in the beginning of this abridgment of the statutes: “You shall fear, every man, his mother and his father, and keep my sabbaths. Those are hopeful children, and likely to do well, that make conscience of honouring their parents and keeping holy the sabbath day. 5. The reason added to both these precepts is, “I am the Lord your God; the Lord of the sabbath and the God of your parents.”
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From John Calvin’s Commentary on Leviticus 18:5:
“You shall therefore keep My statutes and My judgments, which if a man does, he shall live by them: I am the LORD.”
Ye shall therefore keep my statutes. Although Moses introduces this passage, where he exhorts the Israelites to cultivate chastity in respect to marriage, and not to fall into the incestuous pollutions of the Gentiles, yet, as it is a remarkable one, and contains general instruction, from whence Paul derives his definition of the righteousness of the Law, (Romans 10:5,) it seems to me to come in very appropriately here, inasmuch as it sanctions and confirms the Law by the promise of reward. The hope of eternal life is, therefore, given to all who keep the Law; for those who expound the passage as referring to this earthly and transitory life are mistaken. The cause of this error was, because they feared that thus the righteousness of faith might be subverted, and salvation grounded on the merit of works. But Scripture does not therefore deny that men are justified by works, because the Law itself is imperfect, or does not give instructions for perfect righteousness; but because the promise is made of none effect by our corruption and sin. Paul, therefore, as I have just said, when he teaches that righteousness is to be sought for in the grace of Christ by faith, (Romans 10:4,) proves his statement by this argument, that none is justified who has not fulfilled what the Law commands. Elsewhere also he reasons by contrast, where he contends that the Law does not accord with faith as regards the cause of justification, because the Law requires works for the attainment of salvation, whilst faith directs us to Christ, that we may be delivered from the curse of the Law. Foolishly, then, do some reject as an absurdity the statement, that if a man fulfills the Law he attains to righteousness; for the defect does not arise from the doctrine of the Law, but from the infirmity of men, as is plain from another testimony given by Paul. (Romans 8:3.) We must observe, however, that salvation is not to be expected from the Law unless its precepts be in every respect complied with; for life is not promised to one who shall have done this thing, or that thing, but, by the plural word, full obedience is required of us. The pratings of the Popish theologians about partial righteousness are frivolous and silly, since God embraces at once all the commandments; and who is there that can boast of having thoroughly fulfilled them? If, then, none was ever clear of transgression, or ever will be, although God by no means deceives us, yet the promise becomes ineffectual, because we do not perform our part of the agreement.