Saul was . . . years old when he began to reign; and he reigned . . . and two years over Israel.
References for 1 Samuel 13:1
Saul chose three thousand out of Israel; two thousand were with Saul in Michmash and the hill country of Bethel, and a thousand were with Jonathan in Gibeah of Benjamin; the rest of the people he sent home to their tents.
Jonathan defeated the garrison of the Philistines that was at Geba; and the Philistines heard of it. And Saul blew the trumpet throughout all the land, saying, "Let the Hebrews hear!"
When all Israel heard that Saul had defeated the garrison of the Philistines, and also that Israel had become odious to the Philistines, the people were called out to join Saul at Gilgal.
The Philistines mustered to fight with Israel, thirty thousand chariots, and six thousand horsemen, and troops like the sand on the seashore in multitude; they came up and encamped at Michmash, to the east of Beth-aven.
When the Israelites saw that they were in distress (for the troops were hard pressed), the people hid themselves in caves and in holes and in rocks and in tombs and in cisterns.