I have just finished the second week lecture for a course called Judaism, Christianity, Islam, where I looked at the early history of Judaism - beginning with Abraham, the progenitor of all three. Then we looked at others - Moses, David, Solomon, trying to discern underlying principles such as law, order, fear of chaos, a religion of written rules vs one merely lived. I reminded everyone that although we were jumping through centuries in minutes, and talking about grand ideas and movements, that we were in fact dealing with individual people, deciding on the basis of their circumstances - their work, how they lived, family, who they loved, who they hated, desires and wants.
Sorting out the communal from the individual seems impossible. Is religion a matter of public or communal ritual and the human need for fellowship - or is it firstly an individual need for meaning found in a connection to the divine?