What was the sin committed by Saul that cost him his kingdom?
Answer Details
The sin committed by Saul that cost him his kingdom was disobedience. Specifically, he disobeyed God's commandment to completely destroy the Amalekites and all their possessions. Instead, Saul spared the Amalekite king and the best of the livestock, claiming that it was to offer a sacrifice to God. However, God had explicitly commanded him to completely destroy everything, and Saul's disobedience showed a lack of faith and trust in God's instructions. As a result, God rejected Saul as king and chose David to succeed him.