Kenneth B. Alexander 
The Book of First Samuel – Samuel the Prophet Ruled Israel [EPUB ebook] 

Samuel was the first real prophet to rule Israel. He had the unique ministry of being a prophet, a judge and a priest. He established schools of prophets, training young prophets for the purpose of guiding Israel. He, and his prophets, controlled the spiritual realm in Israel and no major decisions were made except by his consultation. When Israel clamored for a King to lead them Samuel anointed the first two Kings of Israel being Saul and David. When Saul proved to be a rebellious King, he anointed David while Saul was still reigning. When Saul proved unworthily to be King, Samuel befriended and protected David as Saul sought to kill him. He was a great man of God who lived his life in constant communication with the Lord and doing what was best for the nation.