Chris Wright, in his very useful commentary on Deuteronomy (NIBC), comments on the “missiological significance” of Deuteronomy (page 8):
Deuteronomy is a book for people on the move, literally at first, spiritually and morally thereafter. It sets Israel on the boundary of the land and looks beyond that boundary to what lies in store for Israel as it moves into the future with God.
Furthermore, it is a book addressed in the name of a God on the move–Yahweh, the God who has been dramatically involved in Israel’s past movements, and indeed also in the movements of other nations on the great chessboard of history.
It presents, therefore, a God of sovereign worldwide purpose and a people with a sharp spiritual mandate and moral agenda.
Earlier Wright fleshes out some of the dynamics between God’s mission and our mission:
[T]he detailed requirements of God on Israel are all founded upon the grace of God manifested in their history. This is not only a structural matter but is also reflected in the way the very vocabulary of Israel’s response to Yahweh in chapters 12-26 mirrors that of Yahweh’s actions toward Israel in chapters 1-11. This [is the] priority of grace and divine action within the covenant framework…