Before they arrived at the plains of Moab, the Israelites fought two major battles and with the help of the Lord won both of them.
Victory Over The Amorites
Israel now sent ambassadors to King Sihon of the Amorites.
“Let us travel through your land,” they requested. “We will not leave the road until we have passed beyond your borders. We won’t trample your fields or touch your vineyards or drink your water.”
But King Sihon refused. Instead he mobilized his army and attacked Israel in the wilderness, battling them at Jahaz. But Israel slaughtered them and occupied their land from the Arnon River to the Jabbok River, as far as the borders of the Ammonites; but they were stopped there by the rugged terrain.
So Israel captured all the cities of the Amorites and lived in them, including the city of Heshbon, which had been King Sihon’s capital. Numbers 21:21-26
As the Jews continued their journey, they arrived at the country of the Amorites. They were descendants of Noah’s son Ham through his son Canaan (Gen. 10:6-15) and should not be confused with the Ammonites. God prohibited Israel from confronting the Ammonites (Deut. 2:18-19) because they were related to the Jews through Lot, Abraham’s nephew (Gen. 19:30-38).
At one time the Amorites ruled vast areas in Mesopotamia and Syria, but in Moses’ day, their territory was much smaller. The Amorites were located on the western shore of the Dead Sea, north of the Edomites, between the Arnon and Jabbock Rivers. In God’s eyes, they were a wicked people, ripe for judgment (Genesis 15:16), and Moses knew that the Lord had promised Israel victory over this evil nation (Ex. 23:23).
The Lord wanted Israel to possess the land east of the Jordan, so He permitted Sihon to attack Israel. Sihon’s capital was at Heshbon, but he and his army came south to Jahaz, about twenty miles north of the Arnon River, and there challenged Israel. God’s people won the battle and possessed the land from the Arnon to the Jabbock River. Before Israel entered the Promised Land, the territory east of the Jordan River was given to Reuben, Gad, and Manasseh (Num. 32).
In Numbers 21:27-30, Moses quoted an Amorite “war song” and applied it to the people of Israel. The song originally celebrated a great Amorite victory when Sihon defeated Moab and took their cities and their people captive. But now it’s Sihon and the Amorites who are the losers. Sihon had conquered Chemosh, the god of the Moabites; but Jehovah had defeated the gods of the Amorites! The first six lines of the song describe Sihon’s victory over Moab, but the last two lines describe Israel’s victory over Sihon.
In writing the Book of Numbers, Moses was led by the Holy Spirit to record this song and apply it to Israel. In fact, the Prophet Jeremiah also quoted part of this song in his prophecy concerning the judgment of Moab (Jer. 48:45-46).
Does this mean that God’s people today can borrow “secular songs” and use them in praising God? No, it doesn’t, for Israel used this “taunt song” on the battlefield, not in the sanctuary. Moses was writing history, not liturgy, and Jeremiah was writing prophecy. Christian lyricists have borrowed secular tunes, but we’re on dangerous ground when we adopt secular words to express our praise and worship to God.
Victory over Bashan
They next turned their attention to the city of Bashan, but King Og of Bashan met them with his army at Edrei. The Lord told Moses not to fear—that the enemy was already conquered! “The same thing will happen to King Og as happened to King Sihon at Heshbon,” the Lord assured him. And sure enough, Israel was victorious and killed King Og, his sons, and his subjects, so that not a single survivor remained; and Israel occupied the land. Numbers 21:33-35 TLB
After a “mop-up” operation around Jazer, Israel turned its attention to Bashan, a very fertile region east of the Sea of Galilee and south of Mount Hermon. During Abraham’s time, people called the Rephaites lived there (Gen. 14:5). Og, king of Bashan, confronted Israel at Edrei, a town about fifty miles northeast of Jazer, but the Lord assured Moses that Israel would win the victory, and they did.
According to Joshua 2:10, the news of this victory spread to Jericho and brought fear to the hearts of the inhabitants. Ezra mentioned this victory in his prayer (Neh. 9:22) and the psalmists in their songs of praise (Ps. 135:11; 136:19-20). Og had his capital in Ashtaroth (Deut. 1:4) and ruled over sixty cities (Josh. 13:30), all of which Israel captured and destroyed, leaving no survivors (Num. 21:35; Deut. 3:1-11).
In their conquest of Canaan, Israel followed the pattern described in Numbers 21:32-35. Joshua would send out spies to get the lay of the land. Then he would seek God’s special instructions for each attack, obey God’s orders by faith, and win the victory. The two times that Joshua didn’t follow this pattern he was defeated (Josh. 7 and 9).
The entire region east of the Jordan River was now in the hands of the Israelites and was eventually turned over to the tribes of Reuben, Gad, and Manasseh (Num. 21:32; Deut. 29:7-8). However, Israel would now confront the Moabites who would adopt a subtle strategy that would bring death to 24,000 Jews.
Bible Exposition Commentary – Be Counted (Numbers)