Was Israel commanded to evangelize the Gentile nations, or to remain separated from them?
Israel was commanded to remain a separated people, not to evangelize the Gentile nations. God emphasized they were not to co-mingle, intermarry, or have dealings with pagan Gentiles. Scripture notes they were never told to go and evangelize them; the turn to Gentiles came later, as shown in Acts 10.
Les explains that the division between Israel and the Gentiles kept getting wider, and God kept emphasizing that the covenant people—the Jews, the Israelites—were not to co-mingle with the Gentiles. They were to be a separated people, not intermarry, and have nothing to do with the pagan Gentiles around them. They were never told to go and evangelize them. Les points out this separation carried all the way into the New Testament. Even in Acts chapter 10, Peter was a law-keeping Jew who refused unclean food and told Cornelius it was an unlawful thing for him, a Jew, to keep company with someone of another nation. But God had shown him something else; God was now going to turn to the Gentiles. Up until that time, it was predominantly only His covenant people.