Moed Katan 19b: How do we know that a mourner is forbidden to get a haircut for 30 days? We learn it out from nazir using the word “pera”. Just as a nazir must go 30 days without a haircut, a mourner must do the same.
מועד קטן יט ע”ב: שלשים יום מנלן? ־ יליף פרע פרע מנזיר: כתיב הכא (ויקרא י׳) ראשיכם אל תפרעו וכתיב התם (במדבר ו׳) גדל פרע שער ראשו, מה להלן שלשים ־ אף כאן שלשים.
Rabbi Moshe Heinemann told the following story: There was a religious Jew who served in the US Army in World War 2, and rose to the rank of major. He attributed his survival to his wearing an amulet written by Rabbi Akiva Eiger, guaranteeing that no weapons would harm him. His superiors were all killed, and so he kept getting promoted to take their places, until he reached major.
After the war, he went into business. Business was not going so well for him, but then the army offered him a contract for $3 million, which would have kept his business alive for a couple of years and helped him very much. The problem was that the army officers in charge of the contract invited him to a cocktail party where he was supposed to say that he was interested in the contract. He was sure that if he went, he would get the contract, but ten days before this party, his father died. This party was to take place during his shloshim, when it is forbidden to shave. And being unshaven is an unforgivable sin in the army. He knew he would have to shave in order to attend.
He went and asked his rav if it was allowed to pay someone $10,000 for the honor of being the sandek at his son’s bris, in order to be able to shave. (The Chasam Sofer in Orach Chaim teshuva 158 permitted a man in his shloshim to shave in preparation for a meeting with a government official where a large amount of money was at stake. He required two other mitigating factors: the day of the shave would have to be Rosh Chodesh, and he would have to serve as a sandek that day.)
This rav, who was known to be a machmir, thought about it and, after some time, said that he would be lenient if two other rabbonim would be lenient as well. He did not want to take responsibility for paskening this shailah all by himself. The man realized that this must be a serious shailah, and so he decided not to pursue it further. He didn’t ask two other rabbonim; he simply decided that he would not shave, not go to the party, and the Ribono shel Olam would send him the yeshua in some other way. His business continued steadily downhill until it was finished.
“What is the moral of the story?” concluded Rav Heinemann. “A person is not really in a position to decide what is a midas chasidus and what is not a midas chasidus. The rav said he would allow shaving if two other rabbonim were to concur with his heter. It is true that maybe the great loss involved was part of the heter, but if that is the din of the Torah, why should you be more machmir? We do find the concept one should be stringent and not eat from an animal that was the subject of a rav’s psak (Chullin 37). But he should have returned to his rav and asked, ‘Do you think that it is the right thing for me to be machmir?’ If the rav had said that he should be machmir, then he would have known he was doing the right thing.”
Source: Ma Nomar, Hilchos Chol Hamoed, page 55
[What is the source for being lenient in the laws of aveilus in order to save a large amount of money? Rav Heinemann contends that it is linked to the concept that one need not give up more than a fifth of his income in order to fulfill a positive mitzvah (Rema Orach Chaim 656:1). Despite the fact that the laws of aveilus are stated as prohibitions, the Chasam Sofer evidently considered them to be positive in nature, enacted by Chazal in order to give honor to the departed.]
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