I put wrote relevant comment to this question. It was even upvoted. Now, both it, and DoubleAA's noticing a typo, are deleted. What happened?
I am not upset, I just want to understand the process.
That was me. I was deleting my response to your comment and your response to my response for being 'too chatty', and decided to just remove yours as well since I didn't see how it helped the question and there were already a number of later comments added (though this appears to have been a short-lived phenomenon). I have deleted over 250 comments in the last month as part of my moderation duties.
I don't really see how a random 4 word phrase in Tanakh that doesn't start a book or even a chapter really helps the question, even if it does have the correct initial lettering. I can find over 20 more like that (eg.), but who cares?
(If people really want I can undelete it. I have no particularly strong feelings here and I certainly care about the community's input.)
I don't know what the nature of your comment was or why it was deleted, but comments are, according to SE doctrine, "temporary 'Post-It' notes left on a question or answer" for the purpose of suggesting improvement to the post they're on. If the comment suggested an improvement, and that improvement was made, then the comment has no more reason to exist, so it's fair game and worthy hygiene to delete it.