Reuben

Reuben was the firstborn son of Jacob and Leah, making him the eldest of the twelve tribes of Israel. His birth is recorded in Genesis 29:32, where Leah names him Reuben, meaning "See, a son," expressing her hope that Jacob would now love her. As the firstborn, Reuben held a position of prominence and responsibility among his brothers.

However, Reuben's actions led to a loss of his birthright. In Genesis 35:22, it is recorded that Reuben slept with Bilhah, his father's concubine, an act that brought disgrace upon him. This transgression is later mentioned by Jacob in his final blessings to his sons, where he says, "Reuben, you are my firstborn, my might, and the beginning of my strength, excelling in honor, excelling in power. Uncontrolled as the waters, you will no longer excel, because you went up to your father’s bed, onto my couch and defiled it" (Genesis 49:3-4).

Despite this, the tribe of Reuben played a significant role in the history of Israel. During the wilderness journey, the tribe was counted among the twelve tribes and participated in the conquest of Canaan. However, Reuben, along with Gad and the half-tribe of Manasseh, requested to settle on the east side of the Jordan River, as the land was suitable for their large herds and flocks (Numbers 32:1-5). Moses granted their request on the condition that they assist the other tribes in conquering the land west of the Jordan (Numbers 32:20-22).

Gad

Gad was the seventh son of Jacob and the firstborn of Zilpah, Leah's maidservant. His birth is recorded in Genesis 30:9-11, where Leah names him Gad, meaning "Good fortune," reflecting her joy at his birth. The tribe of Gad, like Reuben, was known for its warrior spirit and played a crucial role in the military campaigns of Israel.

The tribe of Gad, along with Reuben and the half-tribe of Manasseh, chose to settle on the east side of the Jordan River. This decision is detailed in Numbers 32, where the leaders of Gad and Reuben approach Moses with their request. Moses initially expresses concern that their decision might discourage the other Israelites, but he agrees after they promise to help in the conquest of Canaan (Numbers 32:16-18).

The territory allotted to Gad was known for its fertile land and strategic location. In Deuteronomy 33:20-21, Moses blesses the tribe of Gad, saying, "Blessed is he who enlarges Gad’s domain! Gad dwells like a lion, tearing at arm or head. He chose the best land for himself; the leader’s portion was kept for him. When the heads of the people assembled, he carried out the LORD’s righteous will, and His judgments concerning Israel" .

Throughout the biblical narrative, the tribes of Reuben and Gad are often mentioned together due to their shared geographical location and similar circumstances. Their decision to settle east of the Jordan set them apart from the other tribes, yet they remained integral to the nation of Israel.