As we get closer to Canaan (for the second time), it’s worth thinking about the transformation of the nation of Israel.
If you remember, when Israel came out of Egypt, they were armed, but they didn’t really pose much of a threat. God even led them around Philistine territory because He knew they would get scared and take off (Exodus 13:17-18).
Now, they’re so powerful that entire nations are standing in their way to block them from getting to Canaan. The Edomites prevented them from going through their country, and now the Amorites are doing the same thing.
The major difference between Edom and the Amorites is the aggressive posture Israel took towards the Amorites. Both Edom and the Amorites—led by King Sihon—threaten war if their boundary lines are crossed; Israel only proceeds through the land of the Amorites, “taking possession” of their cities.
This isn’t the first military victory by Israel; that would go to Joshua back in Exodus 17 against the Amalekites. It isn’t even the first one in a long time. Israel had just defeated the Canaanites in the Negev (Numbers 21:1-3).
But it is the first conquest. Instead of simply annihilating their cities, this is the first time that the Bible records Israel “taking possession” of anything (Numbers 21:24).
It doesn’t seem like their acquisition of the Transjordan was really part of the plan, though. In a move that is explained later in Numbers 32, the tribes of Reuben, Gad, and half the tribe of Manasseh, see this land (and the area north along the Jordan River), and want it for themselves. Moses grants it to them on the condition that they continue the conquest of Canaan along with the rest of Israel.
Just because this area has been conquered though, doesn’t mean that it’ll be free from problems. The Ammonites live just on the other side of the border, and will argue Israel’s claim over the Amorite land.
In Judges 11:12-28, the boundary is called into question. A judge by the name of Jephthah responds by saying that the land was lost in battle—that Jehovah gave it to them, just as the Ammonites claim their god Chemosh gives them their land. Ammon has no right to the Transjordan; Israel won it fair and square.
Besides establishing the eastern border of Israel, there’s another reason why this area is so important.
In Numbers 13, when the ten spies give a negative report and the people lose heart, God punishes them by making them wander for forty years instead. Aghast at this thought, they change their minds and attack the Amorites anyways. As Moses describes later, the Amorites chased them out of their land “like bees” (Deut. 1:44).
That didn’t happen this time around. Forty years is a long time—long enough to change a nation—and Israel is ready to take the land of the Amorites. This time, with God at their back, success was inevitable.