Ian is a "steely-eyed rocket man"!  I thanked him off-list in order not to clutter it up, which led to several more exchanges.  I wanted to add my final reply to him to the list in case others find it helpful in the future.

Begin quote:

I couldn't get it to work, but...it may have been that instead of closing the file I was testing on I was rather doing M-x eval-buffer.  It kept giving me errors about entities or something.

However, after reading your links on local variables and more digging around on forums I decided to try footers before trying it in init.el.  Thus, I arrived at:

> # Local Variables:
> # mode: org
> # org-match-substring-regexp: "\\(\\)\\([_^]\\)\\(\\(?:{\\([^{}]*?\\|\\(?:[^{}]*?{[^{}]*?}\\)+[^{}]*?\\|\\(?:[^{}]*?{\\(?:[^{}]*?{[^{}]*?}\\)+[^{}]*?}\\)+[^{}]*?\\)}\\)\\|\\(?:(\\([^()]*?\\|\\(?:[^()]*?([^()]*?)\\)+[^()]*?\\|\\(?:[^()]*?(\\(?:[^()]*?([^()]*?)\\)+[^()]*?)\\)+[^()]*?\\))\\)\\|\\(?:\\*\\|[+-]?[[:alnum:].,\\]*[[:alnum:]]\\)\\)"
> # org-pretty-entities: t
> # End

This also did not work when I evaluated the buffer.  After carefully rereading your last reply and noticing "The test is to save it with an .org extension and open it. When you try to open it, emacs should ask you if you want to load 'values that may not be safe'" I deduced I should close the file and re-open it (duh!).

This time I got the prompt you mentioned, and after accepting the risk, Viola! Rather than attempt it the original way, I think I will keep it as a footer where it is less distracting to me.

Bo, you can try this. I don't know what else it will break, so I did it as
a file local. alternatively you could set `org-match-substring-regexp' in
your init.

---
;;; -*- org-match-substring-regexp:
"\\(\\)\\([_^]\\)\\(\\(?:{\\([^{}]*?\\|\\(?:[^{}]*?{[^{}]*?}\\)+[^{}]*?\\|\\(?:[^{}]*?{\\(?:[^{}]*?{[^{}]*?}\\)+[^{}]*?}\\)+[^{}]*?\\)}\\)\\|\\(?:(\\([^()]*?\\|\\(?:[^()]*?([^()]*?)\\)+[^()]*?\\|\\(?:[^()]*?(\\(?:[^()]*?([^()]*?)\\)+[^()]*?)\\)+[^()]*?\\))\\)\\|\\(?:\\*\\|[+-]?[[:alnum:].,\\]*[[:alnum:]]\\)\\)";
org-pretty-entities: t; -*-

here are some verses where there's a space after the verse number:

^1 In the beginning God created the heavens and the earth. ^2 Now the earth
was formless and empty, darkness was over the surface of the deep, and the
Spirit of God was hovering over the waters.

if you don't want the space after the verse number, you can use curlys:

^{3}And God said, “Let there be light,” and there was light. ^{4}God saw
that the light was good, and he separated the light from the darkness.
^{5}God called the light “day,” and the darkness he called “night.” And
there was evening, and there was morning—the first day.

On Fri, Jul 10, 2020 at 8:33 PM Bo Grimes <vcg3rd@fastmail.com> wrote:

Emacs 26.3, Org-mode 9.1.9, Kubuntu 20.04, 5.4.0-39-generic

Hi,

I've tried my hardest to find an answer in the manuals (print book and
on-line), this list, Reddit, and Stack Exchange with no luck.  I use Emacs
for org-mode, and I don't code or know Elisp.  I have no use for or
interest in learning LaTeX.  I never use subscript, and I only use
superscript in poetry/prose (mostly quotes, not original), and I don't
foresee (but admit I may) a need to export.

I understand that:

^2H is not recognized as superscript _on purpose_. Per Org syntax, you
have to add a non-blank character before the caret. Otherwise, there would
be ambiguity between underline (e.g., _under_) and subscript (_under). And
superscript syntax follows subscript's. [1]

That makes sense to me as a default [2], given that so many org-mode users
use both in math, science, and literate coding context, so I wouldn't think
to suggest it to be changed.  All I want to know is how I can change it for
*me*.

I would like to org-toggle-pretty-entities in a buffer and see superscript
before, say, a poetry line or Bible verse I'm quoting in a note or journal
entry, and not see the non-blank character.

Can this be done via customize or with an Elisp snippet in init.el?

Thanks!

[1] https://lists.gnu.org/archive/html/emacs-orgmode/2014-06/msg01022.html

[2] Though I wish it were made explicit in the manuals
https://orgmode.org/manual/Subscripts-and-Superscripts.html#Subscripts-and-Superscripts
(Org Mode 9 Reference Manual p 132). It took me a while to figure out why
it wasn't working at all.