55 Based on the revelation of the holy sovereign God, this pericope instructs Israel on the form of proper worship of such a God. It focuses on the altar, the centerpiece of worship. The point of the section is this: those who worship this holy God must preserve holiness in the way they worship—they worship where he permits, in the manner he prescribes, and with the blessings he promises. This paragraph is said to open the Book of the Covenant, which specifically rules on matters of life and worship.
56 Heb “and Yahweh said.”

In other versions

And the Lord said to Moses, “Thus you shall say to the people of Israel: ‘You have seen for yourselves that I have talked with you from heaven.

Then the Lord said to Moses, “Tell the Israelites this: ‘You have seen for yourselves that I have spoken to you from heaven:

Then the Lord told Moses, “This is what you are to say to the Israelites: You have seen that I have spoken to you from heaven.

And the Lord said to Moses, “Say this to the people of Israel: You saw for yourselves that I spoke to you from heaven.

And Yahweh said to Moses, “Thus you will say to the Israelites, ‘You yourselves have seen that I have spoken to you from the heavens.

And the Lord said unto Moses, Thus thou shalt say unto the children of Israel, Ye have seen that I have talked with you from heaven.

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