Jazer was a town east of the Jordan River in the region of Gilead.
The Israelites took Jazer and its nearby villages when Moses was their leader (Numbers 21:32). The tribes of Gad and Reuben wanted to live there because the land was good for raising animals. They had many flocks and herds (32:1–5). They promised to build protection for their women and children. Then they would go with the other tribes to fight in Canaan (verses 6–27).
Jazer marked part of the border of the land given to the tribe of Gad (Joshua 13:25). It was also given to the Levites (Joshua 21:39; 1 Chronicles 6:81). Later, Joab came to Jazer when King David sent him to count the people of Israel (2 Samuel 24:5). Jazer is also mentioned when David looked for “capable men” to serve (1 Chronicles 26:31).
About 200 years later, the nation of Moab took control of Jazer (Isaiah 16:6–9; Jeremiah 48:32).