20: that we also may be like all the nations, and that our king may govern us and go out before us and fight our battles."
Note that in wanting "to be like other nations," the Israelites are turning their back on God's rule.
Two students were confused over vv. 19-20 (above). The verses say the people wanted a king in order to be like other nations and so the king should lead the people (better than local charismatic judges, or God). So in this sense they are turning their back on God. They don't trust that God is able to defeat an army, the way God defeated Pharaoh, destroyed Jericho, and all the other victories from God.
To turn one's back means to reject ("I asked him for money; he turned his back on me"). As for being like the other nations, though all nations are under God, God has allowed these nations to do whatever they want. They sacrifice their children for military victory. They bribe their gods for advantage. They worship many gods.
According to the Bible, none of this is real; God proved this by defeating these so-called gods in the past. So why don't the people trust God now? Why do they want to be like the other nations, which God did not choose the way he chose Israel, as his son, or chosen one?
Historically, the reason is shown in the book of Judges. By that time the little nation of Israel was falling apart without a leader. "Everyone did what was good in his own eyes." The spiritual leaders (judges) were also corrupt (Samson); even when righteous, they lacked commitment from all the tribes.
We know this from Deborah's military victory, where her song complains that not all the tribes fought in the battle. Many scholars believe the book of Judges was placed before Samuel in order to "justify" or explain why the Israelites chose a king; because social order was falling part; some degree of centralization was necessary; and wars were becoming too big to rely on small tactics, such as in the book of Joshua (Joshua follows God's orders, blows his horn, and the walls tumble down). The times had changed and the tactics had to change.
We saw the same thing in American history, where there was debate between states' rights and federalization (centralization of government). The American Constitution kept a balance because the states didn't want any interference from a central government (Washington) but the other faction knew that some degree of centralization was necessary, or how to fight a big war? Today many states still complain that the original meaning of "13 united states" has been lost; the federal (central) interferes too much in states' rights.
So Israel would never be the same again, as the prophecy in chapter 8 of 1 Samuel shows: their master would no longer be God but a mere king. They would be slaves again, undoing the freedom from slavery God effected in Egypt.
So the two books of Samuel show this tension between what really happened (kingship, kingdom) and what the authors believed should have happened (that is, following God alone). Since, according to Hebrew theology, God is always in control, the text had to show that God both disapproved but also approved (if reluctantly) kingship.
Of course the two Samuels were written probably after, not before, the events predicted in chapter 8; so the writer could see with 100% vision (after suffering under Solomon's reign) what would happen in the future, because it had already happened.
One final note: in the Christian Bible, the book of Judges is followed by the book of Ruth; but in the Jewish Bible, 1 Samuel follows after Judges, thus making the point more clear: the people had to have a king in order to avoid the mess shown in Judges.
