18:13, 19:19 “You shall be blameless before Yahweh your God; you shall purge evil from your midst”

Israel has been instructed that through their prosperity and righteousness, the nations will see the true God at work in His people. These qualities that bear witness to God’s character will be protected through religious rituals and wise judgments for complex situations. Moses continues to explain these in this section of Deuteronomy. 

After specifying the portion that the people are to give to the Levites, Moses forbids pagan practices that would provide revelation or clarity. Instead, he foretells of a singular prophet like himself that will be the mediator the people requested on Sinai, and will reveal the ultimate standard by which God will judge His people. Israel must anticipate this great figure but also beware of false prophets, and prophets will be distinguished by the outcome of their claims.

After this, Moses revisits procedures for various situations that protect the purity and righteousness of God’s nation. “Purge the evil from among you” is repeated throughout the next three chapters, in cases of murderers, false witnesses, and dishonoring sons. These criminals receive the same consequences as those who would follow after others gods and cultures, and we can deduce from this that gross moral violations are equated to unbelief in the eyes of Yahweh. We also see statutes for success in war and in dealing with the spoils of victory, being reminded that the total apprehension of the sworn land will require faithfulness over a long period of time.