Matthew Henry on 1 Samuel 13:1-7

Saul reigned one year, and nothing particular happened; but in his second year the events recorded in this chapter took place. For above a year he gave the Philistine time to prepare for war, and to weaken and to disarm the Israelites. When men are lifted up in self-sufficiency, they are often led into folly. The chief advantages of the enemies of the church are derived from the misconduct of its professed friends. When Saul at length sounded an alarm, the people, dissatisfied with his management, or terrified by the power of the enemy, did not come to him, or speedily deserted him.