The Arnon River, known in Hebrew as "נחל ארנון" (Nahal Arnon), is a significant geographical feature in the biblical narrative, serving as a natural boundary and a site of historical events. It is mentioned multiple times in the Old Testament, primarily in the context of the Israelites' journey to the Promised Land and the territorial boundaries of the tribes of Israel.

Geographical Location:

The Arnon River is located east of the Jordan River, flowing into the Dead Sea. It originates in the highlands of modern-day Jordan and travels through a deep gorge, marking the border between the ancient territories of Moab to the south and the Amorites to the north. This river is identified today with the Wadi Mujib, a significant watercourse in Jordan.

Biblical References:

1. Boundary Marker:
The Arnon River is frequently mentioned as a boundary marker. In Numbers 21:13, the Israelites camped "beyond the Arnon, which is in the wilderness that extends from the border of the Amorites." This verse highlights the river's role as a dividing line between the Amorite and Moabite territories.

2. Conquest of Sihon:
The river is notably referenced in the context of Israel's conquest of the Amorite king Sihon. In Deuteronomy 2:24, God commands the Israelites, "Rise up, set out, and cross the Arnon Valley. See, I have delivered Sihon the Amorite, king of Heshbon, and his land into your hands." This passage underscores the Arnon as a strategic point in Israel's military campaigns.

3. Tribal Inheritance:
The Arnon also delineates the inheritance of the tribes of Reuben and Gad. In Joshua 13:16, the territory of Reuben is described as extending "from Aroer on the rim of the Arnon Gorge, and from the city in the middle of the gorge, and the whole plateau past Medeba." This allocation of land emphasizes the river's importance in defining tribal boundaries.

4. Prophetic Significance:
The Arnon is mentioned in prophetic literature as well. In Isaiah 16:2, the prophet speaks of the daughters of Moab fleeing "like fluttering birds, like scattered nestlings at the fords of the Arnon," illustrating the river's role as a place of refuge and transition during times of distress.

Historical and Theological Significance:

The Arnon River's role as a boundary and a site of conflict reflects the broader themes of divine promise and fulfillment in the biblical narrative. It symbolizes the transition from wilderness wandering to the establishment of a settled nation in the Promised Land. The river's mention in various contexts highlights God's sovereignty in determining the boundaries of nations and His faithfulness in delivering the land to His chosen people.

In summary, the Arnon River serves as a critical geographical and historical marker in the biblical account, representing both physical and spiritual boundaries in the unfolding account of Israel.