When the woman who escaped from behind the Iron Curtain to the United States said she was married but had received a valid divorce, her new American fiancé was concerned. If she were still married, it would be fruitless to continue the relationship because relations between a married woman and a man who is not her husband are prohibited. But could he rely on her unverified statement that she was divorced when, due to her inaccessible background, there was no way to prove it?
If the Eastern European lady had said nothing, nobody would have known she was once married. It was she herself who was honest enough to volunteer this inconvenient information. Accordingly, the halacha considers her sufficiently credible to qualify her unsolicited statement that she was once married by adding that she received a divorce. This halachic principle is known as Hapeh she’assar hu hapeh shehitir, or simply hapeh, which means the mouth that uttered the prohibition is the mouth that grants the permission.
The principle of hapeh is applied in a situation where a person volunteers unsolicited information about herself, such as “I was married,” when there is no way of verifying such information.
Another application of hapeh is the case of witnesses who testify in court that the signatures certifying to the authenticity of a debtor’s signature on a promissory note are indeed their signatures. However, they immediately qualify their statement and add that they were forced to sign on pain of death. The promissory note under Jewish law is unenforceable in court unless it bears the signature of certifying witnesses who attest that the signature of the debtor on the note is authentic. If the court has no other way of recognizing the signatures of such certifying witnesses except by listening to their own testimony, then, based on the principle of hapeh, the certifying witnesses are believed when they add that they were coerced to sign. The result would be that the promissory note is unenforceable.
Whereas, according to most halachic opinions, the qualifying statement of the litigant herself, such as the lady in the case described above, may be made some time after her initial statement, the qualifying statement of a witness must be made immediately – toch kedey dibur.
Some consider the principle of hapeh to be a subset of the principle of migo. The migo principle says that a court should believe the statement of a litigant in his own defense where he could have come up with a better defense. For example, plaintiff sues defendant and claims he lent the defendant money. But plaintiff does not produce an enforceable promissory note because defendant’s signature on the note is not certified by witnesses. Now defendant admits to the court that he borrowed the sum of money referred to in the promissory note but claims, in his defense, that he already repaid it. Had the defendant been lying he could have invented a better lie, namely, that the plaintiff never lent him any money or that his signature on the unauthenticated promissory note was forged.
As long as the defendant would have been prepared to take a rabbinical oath, shevuat hesseit, that he never borrowed any money from the plaintiff, the defendant, in the absence of a valid promissory note, would have won the case. Thus, if defendant chose the weaker defense of “Yes, I borrowed money from you but I repaid you,” he must be telling the truth and the court, based on the principle of migo, will rule in his favor. The principle of hapeh, then, is also a form of migo, because had the lady wanted to lie, she could have just remained silent.