"Great calamity" refers to a severe and devastating event or disaster that causes immense suffering or harm to a large number of people or things. Full definition
The getting that (favour) leads to the apprehension (of losing it), and the losing it leads to the fear of (still greater calamity): — this is what is meant by saying that favour and disgrace would seem equally to be feared. (religion-online.org)
Common wisdom asserts that heroes are born from great calamity, and yet our Charlotte's early life was pretty standard. (bookpage.com)
Who's to say that some great calamity was not meant to occur but was averted because of prayers? (religion.blogs.cnn.com)