1 Samuel 10:25
Then Samuel told the people the manner of the kingdom, and wrote it in a book, and laid it up before the LORD. And Samuel sent all the people away, every man to his house. Then Samuel told the people the manner of the kingdom, and wrote it in a book, and laid it up before the LORD. And Samuel sent all the people away, every man to his house.
Samuel set out the principles that were to govern Israel under a monarchy and wrote them down in a book. The king was not to rule as an absolute monarch, but was to exercise his authority in subjection to the will of God. That written record defined on the one hand the rights and prerogatives of the ruler and on the other the rights and privileges of the people. By fixing both in writing, it was meant to safeguard the liberties of the nation against any future abuse of royal power. Even though Israel had rejected the warning against taking a king, Samuel still took this step to protect the liberties of the people.
At that time the greater part of the people accepted Saul as king. Others refused him allegiance and withheld the customary gifts, because they resented the choice of a king from Benjamin and preferred different candidates. Envy and pride and disappointed ambition thus turned the appointment of the king into an occasion for faction and discontent.