I perused the comments on this matter just recently and, as I have always said, people on this website do NOT learn, they just parrot what they MIGHT have heard. Mr. Geshmakenstein’s latest posting is a perfect example of this.
He writes (and oomis1105 repeats it): ‘yichud is prohibited [with an unmarried woman] and has the severity of yihud d’oraisa ,due to her being a nidah”.
I don’t know know where Mr. geshmakenstein learned his gemoro and halachos but his facts are WRONG. Mi-d’oraisa ,only yichud with an ‘ervah” or married woman is prohibited. “bais din shel dovid gozru al hapenuyah”. The Bet Din of dovid hamelech forbade yichud with a “pnuyah” (unmarried woman)because of the story of Amnon and Tamar. (look it up ,geniuses)
Additionally, what does the maamar ‘kallah belo berocho…” have to do with anything? This is only an admonishment to have chupah vekiddushin and make the birchos nisuin. Nothint to do with yichud.
oomis1105, don’t be taken in by people who don’t know what they are talking about. And a kallah ,as far as I know, is never called an “ervah”. To answer one of the questioners,(lgbg) ‘ervah’ takes its name from the parshyot in vaYikro who describe the forbidden relationships and are mainly the family forbidden connections. It does include a “niddah” (Vayikro 18)The possuk calls them all “ervah”.