Joshua introduced what follows as the words of Yahweh, Israel's God (v. 2).
Then he reviewed God's great acts on behalf of His people going back to the call of Abraham in Mesopotamia.
The "River"(v. 2) is the Euphrates. Abraham's family members were idolaters in Mesopotamia. We can safely assume that Abraham was too. God's call of Abraham was pure grace. There was nothing in Abraham that resulted in God choosing him for special blessing. Joshua probably mentioned Nahor because Rebekah, Leah, and Rachel descended from him. Two of the nations that had come out of Abraham were Israel and Edom (v. 4).
The Exodus was a second great proof of God's grace to Israel (vv. 5-7). The provision of Moses and Aaron as well as the sending of the plagues were special gifts then. Israel's deliverance from Egypt and her preservation in the wilderness were also highlights of God's faithfulness during this period of Israel's history.
God's third great act for Israel was the Israelites' victory over the Amorites east of the Jordan (vv. 8-10). God also frustrated Moab's hostility by turning Balaam's oracles into blessings.
The fourth divine provision was the crossing of the Jordan River and the consequent victory over the Canaanites (vv. 11-13). God routed Israel's enemies for her by using various hornet-like terrors (v. 12; cf. Exod. 23:28; Deut. 7:20).
In this section of verses (vv. 2-13) God said 17 times "I"did such and such for you. The emphasis is clearly on God's great acts for Israel.
