The tribes of Reuben and Gad, and some Manasseh-ites want to settle in the land just conquered, east of the Jordan. Moses doesn't like it, at first, seeing the same rebellion Israel committed 40 years ago. They must go fight for Israel west of the Jordan, then they may settle back here.
God recounts all the places Israel camped for the last 40 years, and tells them to be sure to drive out all the inhabitants and smash their idols. Anything they leave alone, will ensnare them later, and God will drive Israel out, too.
How this is about Jesus
The Psalms are full of language about Christ ruling and defeating His enemies. Psalms 2 and 110 are good examples. Revelation 19, also.
- We must show no mercy or pity to the remnants of sin left in our hearts, families, or churches. One Puritan said, "Be killing sin, or it will be killing you."
- How did these tribes know they had found their inheritance? The land fit their possessions of cattle. Sometimes God guides by circumstances, IF we will also follow His revealed Word in that situation (in this case, fighting for the rest of Israel, and protecting your families).