| Gill's Exposition of the Entire Bible And ye shall keep my statutes, and do them,.... Not only those respecting the above things, but all others, which would be a means of preserving them from sin, and of promoting holiness in their lives and conversations: I am the Lord which sanctify you: who had separated and distinguished them from all other people on earth, and who had given them holy laws, as the means of holiness; and who only could and did sanctify internally, by his Spirit and grace, such or them as were sanctified in heart, as well as outwardly.
Geneva Study BibleAnd ye shall keep my statutes, and do them: I am the LORD which sanctify you.
Wesley's Notes 20:8 Who sanctify you - Who separate you from all nations, and from their impurities and idolatries, to be a peculiar people to myself; and who give you my grace to keep my statutes.
Matthew Henry's Concise Commentary20:1-9 Are we shocked at the unnatural cruelty of the ancient idolaters in sacrificing their children? We may justly be so. But are there not very many parents, who, by bad teaching and wicked examples, and by the mysteries of iniquity which they show their children, devote them to the service of Satan, and forward their everlasting ruin, in a manner even more to be lamented? What an account must such parents render to God, and what a meeting will they have with their children at the day of judgment! On the other hand, let children remember that he who cursed father or mother was surely put to death. This law Christ confirmed. Laws which were made before are repeated, and penalties annexed to them. If men will not avoid evil practices, because the law has made these practices sin, and it is right that we go on that principle, surely they should avoid them when the law has made them death, from a principle of self-preservation. In the midst of these laws comes in a general charge, Sanctify yourselves, and be ye holy. It is the Lord that sanctifies, and his work will be done, though it be difficult. Yet his grace is so far from doing away our endeavours, that it strongly encourages them. Work out your salvation, for it is God that worketh in you. | 
