It seems that the typical practice is to link related questions in a comment on the question, but I seem to recall reading that the comments are not exposed to search engines and I think links are an important part of how search engines optimize results.
So, should such links be edited into questions or left as comments? Also, if they should be edited into the question, how should they be presented? (E.g., one might have a separate "section" at the bottom with "Related questions:" or "Possibly related questions:"--or one might try to provide better flow, e.g., "Unlike Why X?(link), this question seeks an answer in this specific context" or "When was X first done(link) does not address later occurrences", though better flow is more difficult, perhaps especially for a question.)
This might well be a question for meta.stackexchange (I only searched meta.christianity), though different SEs might have different preferences and expectations.
From the Stackoverflow FAQ
The "What about similar or related questions?" section of this answer to the question "How should duplicate questions be handled?" indicates one should have a section with a h3 (three # marks) header (with the text "See also") with the question title as the link text.
(In some cases, I think a brief parenthetical description/explanation might be appropriate to clarify the relationship. This would seem to especially apply when linking to one answer; if other decent answers to a question are not sufficiently related, the question title by itself is likely to be less helpful.)
