If you want to explain what is less clear, you must fall back on what is more clear.  Certainly there is a lot to learn from the biblical narrative, but one must interpret it in the light of the doctrinal statements, not vice versa.  To set aside explicit teachings and rely on the stories alone is just a way to pipe in one’s own prejudices and call them the teachings of the Bible.  Anything goes.

Obviously this traditional approach wouldn’t work if we were dealing with inconsistent texts – for example if grandpa said “Never steal,” but spun tale after tale of thieves getting the best of honest folk.  But the premise of Scripture is that God, always truthful, is consistent.  What He teaches by story, statement, and precept cannot be divided.