The 1883 Krakatoa eruption and the 2018 tsunami that hit the coast of Banten and Lampung are among the most memorable disasters in Indonesian history. One occurred during the colonial period when technology had not yet reached the sophistication it has today, and the other when technology was very advanced. This research aimed to see what religious issues developed in the 1883 Krakatoa eruption and the 2018 tsunami. The historical method of heuristic, criticism, interpretation, and historiography is employed in this study. Through a literature review, the data was gathered. Through three methods—genetic, historical parallelism, and comparative—the past and present are linked. The approach in this research compares the similarities and differences related to religious issues related to disasters in two different periods and events. Religious issues, given those who believe in them, play an essential role in the causes and effects of disasters. Religious issues that can be read in these two events range from forms of religious fanaticism to religious sentiment. Understanding religious issues related to disasters from a local perspective will help plan disaster mitigation appropriately amidst the short memories of communities in disaster-prone areas.