Does Logos have a feature where I can find references to the concept of "gospel" even though the actual word is not used? I believe Logos has a feature for characters that does something like this.
Try entering gospel in the Factbook and explore some of the options presented there. That could provide a good starting point
You probably want the topic rather than the preaching theme
This feature gives you results from both topic and preaching theme ... and cultural concept when it applies and ...
This was very helpful! Thank you!