Why? Because the Christian view was that God was a reasonable God, and He made the universe. And because He also gave us reason when He made us, we should be able to understand the universe by reason. All these men, from Newton down to Faraday, looked at the universe and expected to be able to find out how it worked, because of their religion.
Their religion didn't lead them to a non-scientific worldview. Their religion led them to create the scientific worldview.