It is written for the carnal, so that those that cannot move beyond being of the world have laws to live by and will get along with each other. The Bible will be for teaching them who God is, what He expects and the many lessons He has for us. For these, the Bible is very literal and historical.
It is also written for the Spiritual (those in Christ, those in this world but no longer of this world), so that they know what God expects of their Spiritual being. For these, they have moved beyond the literal meaning and have found Godís Spiritual lessons also. The Bible has become two in one.