What's the most convincing thing that could happen to convince a small group of people holding bigoted views that those views are indeed blessed and chosen by God?
I'm trying to have a small growing religion with discriminatory social views (this is a late 20th century setting) suddenly gain faith when something which looks divine happens, reinforcing their ultra-bigoted views.
Importantly it's not really divine, just looks that way. And not a fraud, just some random event that causes a groups racist / sexist / homophobic / transphobic / etc views go from faith-based to basically-proven "fact".
Edit: I'm not looking for an opinion on what would convince you - I know some people are convinced by their toast burnt to look like Mary. I'm trying to work out what would fortify the beliefs of a decent group (say 500 people).