Deu 2:8 So we went on, away from our brothers, the people of Esau, who live in Seir, away from the Arabah road from Elath and Ezion-geber. “And we turned and went in the direction of the wilderness of Moab. And the LORD said to me, ‘Do not harass Moab or contend with them in battle, for I will not give you any of their land for a possession, because I have given Ar to the people of Lot for a possession.’ (The Emim formerly lived there, a people great and many, and tall as the Anakim. Like the Anakim they are also counted as Rephaim, but the Moabites call them Emim. The Horites also lived in Seir formerly, but the people of Esau dispossessed them and destroyed them from before them and settled in their place, as Israel did to the land of their possession, which the LORD gave to them.) ‘Now rise up and go over the brook Zered.’ So we went over the brook Zered. And the time from our leaving Kadesh-barnea until we crossed the brook Zered was thirty-eight years, until the entire generation, that is, the men of war, had perished from the camp, as the LORD had sworn to them. For indeed the hand of the LORD was against them, to destroy them from the camp, until they had perished.
The Moabites were also distant relatives to Israel; they descended from Lot, who was the nephew of Abraham. And as with Edom, God did not want Israel to harass Moab, nor contend with them in battle – their land was not the land God intended to give Israel. One of the more famous Moabites in the Bible was Ruth. She was a Moabite woman who married an Israelite man named Boaz and became grandmother to King David and one of the ancestors of the Messiah.
The Moabites were of note because they defeated a Canaanite people known as the Emim, who were a large, fearsome race as were the Anakim. The term translated giants here is actually the Hebrew word rephaim. The term rephaim is often translated “giants,” but it actually means “fearsome ones.” The Rephaim were a group of large, warlike people who populated Canaan before the Israelites. In the area east of the Jordan River. (Guzik)
We have the origin of the Moabites, Edomites, and Ammonites. Moses also gives an instance older than any of these; the Caphtorims drove the Avims out of their country. These revolutions show what uncertain things wordly possessions are. It was so of old, and ever will be so. Families decline, and from them estates are transferred to families that increase; so little continuance is there in these things. This is recorded to encourage the children of Israel. If the providence of God has done this for Moabites and Ammonites, much more would his promise do it for Israel, his peculiar people. Cautions are given not to meddle with Moabites and Ammonites. (Henry)
For this reason Israel was to remove from the desert of Moab (i.e., the desert which bounded Moabitis on the east), and to cross over the brook Zered, to advance against the country of the Amorites (see at Numbers 21:12-13). This occurred thirty-eight years after the condemnation of the people at Kadesh (Numbers 14:23, Numbers 14:29), when the generation rejected by God had entirely died out (תּמם, to be all gone, to disappear), so that not one of them saw the promised land. They did not all die a natural death, however, but “the hand of the Lord was against them to destroy them” (Keil)
For indeed the hand of the Lord was against them,…. His power was exerted in a way of wrath and vengeance on them, for their murmurings at the report of the spies; and therefore, it is no wonder they were consumed, for strong is his hand, and high is his right hand; and when lifted up it falls heavy, and there is no standing up under it, or against it: it smote them with one disease or another, or brought one judgment or another upon them: as the sword of Amalek, by which many were cut off, and the plague at Shittim in the plains of Moab, in which died 24,000; besides the destruction of Korah and his company, which was quickly after the affair of the spies, and the plague at that time, of which died 14,700; and thus, by one stroke after another, he went on to destroy them from among the host until they were consumed, even all of them but two. (Gill)