Conversation so far:
When did Parsons attend Heidelberg?
Parsons went on to the University of Heidelberg, where he received his Ph.D.
in sociology and economics in 1927.
What was his best work?
Parsons read extensively in religious literature, especially works focusing on the sociology of religion.

Question: Why was sociology of religion so important?
Self-contained rewrite: Why was sociology of religion so important to Parsons?