Theories differ over whether religious and secular worldviews are in competition or represent overlapping and compatible frameworks. Here we test these theories by examining homogeneity and overlap in Christian and non-religious people’s explanations of the world. Christian and non-religious participants produced free text explanations of 54 natural and supernatural phenomena. Using a new text analytic approach, we quantitatively measure the similarity between 7613 participant generated explanations. We find that the relative homogeneity of Christian and non-religious people’s explanations vary depending on the kind of phenomena being explained. Non-religious people provided more similar explanations for natural than supernatural phenomena, whereas Christian explanations were relatively similar across both natural and supernatural phenomena. This challenges the idea that religious systems standardize and restrict people’s worldviews in general, and instead suggest this effect is domain specific. We also find Christian and non-religious participants used largely overlapping concepts to explain natural and supernatural phenomena. This suggests that religious systems supplement rather than compete with secular based worldviews, and demonstrates how text analytics can help understand the structure of group differences.