The idea behind this episode's plot likely comes from the Peter David "Supergirl" run. In this title, Supergirl was not Kara Zor-El, but a young woman named Linda Danvers who develops divine abilities and becomes a heavenly being, the Earth-Born Angel of Fire. Linda eventually discovers a Church of Supergirl that has been founded in devotion to her.
Chad Lowe plays Thomas Coville. In "Nevertheless, She Persisted (2017)", Cat Grant mentions twice turning down marriage proposals from his brother Rob.
The opening prelude is a flashback using a modified scene from the pilot episode.
The aerial view of the hockey arena is actually showing the Georgia Dome in Atlanta.