What does Frightful is must be for supremely frightful would be the effort of any human endeavor to mock the stupendous mechanism of the Creator of the world mean?

Because Mary Shelley was religeous and when Jesus died God described his death as frightful. and she is mocking gods Words to relate to The Bible. Mary Shelley was from a religious family and it would be a shock to the family that she is doing this. However she is wanting to shock the reader and cause question.