John Calvin Commentary Leviticus 19:36

"Just balances, just weights, a just ephah, and a just hin, shall ye have: I am Jehovah your God, who brought you out of the land of Egypt." — Leviticus 19:36 (ASV)

I am the Lord your God. In these first four passages, he addresses the same points that we have observed in the preface to the Law. For he reasons partly from God’s authority, that the Law should be reverently obeyed, because the Creator of heaven and earth justly claims supreme dominion; and partly, he presents to them the blessing of redemption, so that they might willingly submit themselves to His Law, from whom they have received their safety.

For, whenever God calls Himself Jehovah, it should suggest His majesty, before which all should be humbled, while redemption should of itself produce voluntary submission.

At the beginning, he repeats the same words that he had recently used and then exhorts them to observe His statutes and judgments, that is, to treasure them diligently in their minds. Afterwards, he reminds them why they should attentively observe the Law, namely, that they may perform the works that God requires in it.

Nor is it without reason that at the end of the second verse He declares Himself to be Jehovah, because it is not easy either to subdue rebellious minds or to retain fickle ones in the fear of God. In the next verse, the qualification “which sanctify you” is added, to earnestly arouse them to prove their gratitude to God, who has by a special privilege separated them from the rest of mankind.