1 The reason of three years of famine. Then there was a famine in the days of David three years, year after year; and David inquired of the LORD.

2 Samuel 21:1 The reason of three years of famine. Then there was a famine in the days of David three years, year after year; and David inquired of the LORD. And the LORD answered, It is for Saul, and for his bloody house, because he slew the Gibeonites. They must have happened before the rebellion of Absalom. “In the days of David” seems purposely indefinite. Three years. A famine enduring for three successive years was alarming enough to awaken attention and to suggest some especial cause (Ellicott). Enquired of the Lord. Hebrew "sought the face of the Lord," quite a different phrase from that so often used in Judges (Judges 1:1; Barnes). Probably it means that he went to Gibeon to pray in the sanctuary and consult God by Urim and Thummim (Pulpit). God soon informed him that this punishment was on account of the blood shed by Saul and his family. Because Saul slew the Gibeonites when he slew the priests at Nob. Gibeonites were hewers of wood and drawers of water for the temple ministry. This also many refer to other action of Saul, who sought to root them out of the land. Even heathens had the same notion that barrenness, unfruitfulness, and famine, were inflicted by God for murder. (Gill; Benson). And for his bloody house . Literally, "the house of blood," i. e., the house or family upon which rests the guilt of shedding innocent blood (Barnes).  Quest. Why did not God punish Saul while he was alive for this fault, but during his innocent children in the age of David?  Answ. First, God did severely punish Saul for this and his other sins.  Secondly, God may justly inflict temporal punishments upon any offender, either in his person or in his posterity. Thirdly, The Israelites might make themselves guilty of Saul’s sin by advising or encouraging him to it; or by assisting him in the execution of it for some worldly advantage which they received or expected from it.  Fourthly; It is also to give the world thereby assurance of a future judgment, and punishments reserved for the next life.