These are the words of the covenant that the LORD commanded Moses to make with the Israelites in the land of Moab, in addition to the covenant He had made with them at Horeb.
Now that Moses had largely repeated the commands which the people were to observe as their part of the covenant, and the promises and threatenings which God would make good (according as they behaved themselves) as part of the covenant, the whole is here summed up in a federal transaction.
Commenting on Deuteronomy 29:1-9
These are the words of the covenant,.... Not what go before, but follow after, in the next chapters, to the end of the book; in which are various promises of grace, and promises of good things, both with respect to Jews and Gentiles, intermixed with other things: which the Lord commanded Moses to make with the children of Israel in the land of Moab; or...
These [are] the words of the covenant, which the LORD commanded Moses to make with the children of Israel in the land of Moab, beside the covenant which he made with them in Horeb. (a) That is, the articles, or conditions. (b) At the first giving of the law, which was forty years earlier.