Two Types of Moral Lesson
I would like to differentiate between two types of moral lesson. I would like to call the first an 'objective moral lesson' while the second type will be a 'subjective moral lesson'.
Objective Moral Lesson
This is were one finds an unambiguous moral lesson within the text of the bible. So for example if someone was to tell me that the Torah finds child sacrifice immoral, I would be happy to agree with him. Indeed the Torah explicitly forbids child sacrifice.
Subjective Moral Lesson
This is where one reads a passage in the Torah and then begins to wax lyrical about the great moral lesson one finds there. But wait a minute; is the Torah really trying to express this idea, or is it you who is projecting your own moral idea onto the Torah's narrative. Agreed your own moral idea might evolve in your mind through this process, but this does not mean that the Torah actually came to tell us this idea. You happen to respect The Bible as a Godly book and therefore you use the Bible as a tool to develop your own moral ideas. But you probably could do the same by using any volume of Harry Potter or even Curious George.
My contention is that the vast majority of moral lessons we glean from the Torah are subjective and not objective.