[vladimir998]

“So I’m pretty sure C.S. Lewis’ advice wasn’t an “evensong message”, either.”

If you want to use definitions, then it wasn’t a sermon either:

https://www.google.com/search?q=sermon+definition&rlz=1C1GCEA_enUS802US802&oq=sermon+definition&aqs=chrome..69i57j0l5.3142j1j4&sourceid=chrome&ie=UTF-8

[BillyBoy]

Perhaps he gave a homily instead? Most people use the words "sermon" and "homily" interchangeably, but note the difference in the dictionary definition of homily:

a religious discourse that is intended primarily for spiritual edification rather than doctrinal instruction; usually a short lecture or discourse on or of a moral theme