Ok, so change everything back the way it was before Podz’s suggestion.
Solution:
Go to this post:
https://www.sandiegochurches.org/2004-11/22/the-vertex/
Now, delete the apostrophes and quote marks in the quote and replace them with your own (enter them again). Save the edited post and check your feed again. it should be fine.
Explanation:
FeedValidator gave you this error, “Your feed appears to be encoded as “UTF-8”, but your server is reporting “US-ASCII””. While FeedValidator is the best feed validator, this error is often incorrect. If you get that error, check your feed at https://validator.w3.org/ . The resulting error was:
“Sorry, I am unable to validate this document because on line 142 it contained one or more bytes that I cannot interpret as us-ascii (in other words, the bytes found are not valid values in the specified Character Encoding). Please check both the content of the file and the character encoding indication.”
I downloaded your feed and checked line 142. Sure enough, curly quotes and apostrophes (it’s almost always quotes and apostrophes, especially if you’re copying from another site). Basically, these characters are not part of UTF-8 encoding. If you delete them and replace them with your own UTF-8 apostrophes and quote marks, your feed will be fine again. If FeedValidator continues to display the error, go to https://validator.w3.org/ to find which line the problem character is on, and repeat the process.
This always happens to me quite often because I do a lot of copying from other sites when I post (yes, I always cite the source).