Interestingly two persons named Saul, from the tribe of Benjaminite, were chosen by God. (I Samuel 9:21; Philippians 3:5) The first was to establish the earthly kingdom of Israel, he failed. The second to establish the Kingdom of God. Of course, Saul the Paul succeeded in preaching the gospel, making disciples, establishing churches, and developing leaders.
King Saul: After nearly four hundred years of Judges, the Israelite were not happy. Like other nations, they wanted to have a king: appointed or elected. Prophet Samuel was upset by the demand that the people reject God as their king. God spoke to Samuel and said that the Nation of Israel has not rejected Samuel, but indeed God Himself. Samuel need not be upset, if there is a person who should be upset, it is God. (I Samuel 8:4-9) God guided Samuel to appoint a king. Saul, a Benjaminite who was on a search operation to retrieve his lost donkeys, was called to lead the Nation of Israel. He was physically fit, tall and was able to lead the Nation of Israel but failed. He disobeyed and rebelled against God, and the Nation was not strong. (I Samuel 15: 22-23) He was not willing to fight Goliath, but fighting with David was unnecessary and gave him little time or opportunity to make Israel a great nation.
Persecutor Saul becomes Apostle: Saul, who was zealous for the Law, persecuted the disciples of the Lord. He went to an extent of receiving orders from the High Priest and going city after city to persecute the followers of the Way. During one of his trips to Damascus, he met the Lord and his life was turned upside down. He was called to establish the Kingdom of God by opening the eyes of people blinded by Satan, delivering them from Satanic oppression and bringing them into the Kingdom of God. He pursued that vision taking the gospel to the nook and corners of the Roman Empire. He could confidently assert that he was not disobedient to that heavenly vision. (Acts 26:16-19)
Obedience is an absolute necessity for fulfilling God’s will.