The 3rd Archetypal Step: Moses and the Women of the Well

After killing the Egyptian, witnessing Hebrew on Hebrew injustice, and fleeing Egypt for an under-the-radar life of a shepherd-for-hire, Moses confronts the third of his three searing experiences of injustice:  the bullying of Midianite shepherd girls by the boys.  "And he rises to their defense."  What is the significance of this third archetypal step?  How has his life led up to his moment, and how does this moment continue to define it?  How does it, and his marriage, shape not only his life but his imminent enlightenment at the Burning Bush?