Conversation so far:
When did Talcott Parsons attend Heidelberg?
In June, Parsons went on to the University of Heidelberg, where he received his PhD in sociology and economics in 1927.
What was Talcott Parsons's best work at the University of Heidelberg?
Parsons wrote his Dr. Phil. thesis on The Concept of Capitalism in the Recent German Literature, with his main focus on the work of Werner Sombart and Weber
Why was sociology of religion so important for Talcott Parsons?
his upbringing with a liberal but strongly-religious father had made the question of the role of culture and religion in the basic processes of world history

Question: Why did he concentrate so much on religious literature?
Self-contained rewrite: Why did Talcott Parsons concentrate so much on religious literature?