What was a central idea in thomas aquinas's summa theological?

A central idea was that faith and reason do not contradict each other.

Explanation:

In Summa Theologically, Thomas Aquinas attempted to resolve the points of conflict between faith and reason. He spent seven years writing this work, which was never completed, for the primary purpose of teaching that faith and reason do not contradict one another but complement one another.

By adopting the principles and concepts of the Greek philosopher Aristotle, Aquinas attempted to explain the origin, functioning, and purpose of the universe. He never doubts the truth of the principles of his faith. Instead, it employs techniques of argumentation which it has learned from Aristotle's teachings to affirm, defend, and elaborate such principles.