Can’t download episodes from your feed

This is the URL of your top episode's media file"

http://media.haomuren.org/AudioBible/OT 01 Ge/Ge 01.mp3

You are not allowed spaces in a URL, so iTunes is seeing the URL as ending at the first space and thus it obviously doesn't work. You will need to go through all the episodes and rename the files to remove the spaces - the usual practice is to substitute underscores - and then amend the feed to match. You could get away with simply amending the feed to enter the code %20 in place of each space: that will work (and there is less to do), but it's bad practice to have spaces in your filenames anyway, so it's up to you. But you need to do one or the other or you won't get anywhere.