310 Disclosing Information to a Prospective Shidduch
There are serious halachic ramifications if either party to a shidduch withholds pertinent information— whether aspects of their past life, medical issues, or other relevant facts—fearing that disclosure might be embarrassing or impede the potential shidduch. One of the issues is the issur of ona’ah (deception). Just as in business matters one may not deceive another, likewise in a shidduch, which is halachically a transaction, withholding information is considered ona’ah. At times, there could also be the possibility of mekach ta’us: Just as a purchase based on fraudulent information is not binding, a shidduch based on misinformation—in certain extreme cases—could potentially render the marriage halachically null and void, which is a very grave matter. While the annulment of a marriage is rarely practiced, this principle serves to highlight the potential severity of withholding information.
As a general rule, it is forbidden to hide information for the sake of a shidduch, unless one is certain that when it will be revealed to the other party, they would be sovar vekibel (accept it and not mind). In our times, numerous poskim advise against withholding information that would be considered important. Even to save a shidduch, one should avoid embellishing the facts, and certainly one may not lie outright.
Additionally, in the case of a woman who has previously had a relationship with a man, it could have bearing on whom she may marry and on the kesubah. She should speak with a rav for advice on how to pass on that information to the prospective chosson in a discreet and sensitive manner. While it doesn't bear the same halachic significance, obviously, a man who has had a prior relationship must be equally forthcoming to his prospective kallah.