Nedarim 37a: One who hires someone to babysit a child, to guard a cow or to guard a field of produce, may not pay him for Shabbos. Therefore, if a loss occurred on Shabbos, he is not liable. But if he was hired for the whole week, the whole month, the whole year or the whole seven years, one may pay him for Shabbos. In this case, if a loss occurred on Shabbos, he is liable.
Shulchan Aruch Orach Chaim 306:5: Some forbid hiring a chazzan for Shabbos, and some permit. Rema: If he was hired for a year or a month (and he sometimes leads the davening during the week) it is permitted according to all.
Mishnah Berurah: The Acharonim say that the custom is to be lenient and hire him just for Shabbos. If one wishes to be strict, [one can either use the Rema’s solution and hire him to daven sometimes during the week, or else] one can avoid quoting a price, and whatever he receives will be considered a gift.
נדרים לז ע”א: השוכר את הפועל לשמור את התינוק, לשמור את הפרה, לשמור את הזרעים ־ אין נותנין לו שכר שבת, לפיכך אם אבדו אינו חייב באחריותןֹ ואם היה שכיר שבת, שכיר חדש, שכיר שנה, שכיר שבוע ־ נותן לו שכר שבת, לפיכך אם אבדו חייב באחריותןִ.
או”ח ש”ו ס”ה: אסור לשכור חזנים להתפלל בשבת ויש מי שמתיר: הגה ואם שכרו לשנה או לחודש לכ״ע שרי (ד״ע) :
משנה ברורה: ויש מי שמתיר. ס״ל דבמקום מצוה לא גזרו רבנן על שכר שבת בזה ומ״מ אינו רואה סימן ברכה… ואם שכרו לשנה או לחודש לכולי עלמא שרי. פירוש, לשנה שיתפלל גם בימות החול ומשלם לו לחודש או לשבוע בבת אחת. ועיין באחרונים שכתבו שנוהגים להקל לשכור לשבתות לחוד והחושש לדברי האוסרין לא יקצוב בתחלה ומה שלוקח אח״כ י״ל שהוא דרך מתנה.
או”ח תקפ”ה ס”ה: הנוטל שכר לתקוע בר״ה או כדי להתפלל או לתרגם בשבתות וי״ט אינו רואה מאותו שכר סימן ברכה.
Rabbi Moshe Heinemann related that when he was in yeshiva in Lakewood, there was a bochur with a unusually nice voice, and the main shul of Lakewood wanted to hire him as a chazzan. However, he did not want to take the job because his main responsibility would be leading the davening on Shabbos and Yom Tov, and Chazal say that if a person takes money for working on Shabbos and Yom Tov, he will not see a siman bracha from the money.
Rav Heinemann and his other friends pushed him to go and ask the shailah to the Rosh Yeshiva, Rav Aharon Kotler zt”l. The Rosh Yeshiva said, “In Lakewood it is not easy to get a job. This is an easy job where you will daven on Shabbos and do an hour of choir practice during the week, with no strenuous work on your part. The Ribbono Shel Olam is giving you the opportunity to get married, have a parnassah, and sit and learn for many years. Since you will do it l’shem shamayim, you will see a siman bracha from it.”
But the bochur did not listen, because the Shulchan Aruch says you will not see a siman bracha from working on Shabbos and Yom Tov. He had a very hard time finding a shidduch. He sat and learned until age 28, and then he decided that if he had a job then it would be easier for him to find a shidduch. He did not really find such a great job. Eventually he got married in his thirties, did not have any children, and finally got divorced from his wife. He did not see any siman bracha.
Rabbi Heinemann concluded, “My Rosh Yeshiva told him to take the job and he would see siman bracha. This bochur did not listen because he thought he was smarter. When it comes to things that have to do with ruchniyus, halacha, or hashkafa, a person should not rely on himself. He should rely on people who are big experts, just as a person with a health question should go to a doctor rather than figure it out himself from a book. If he thinks he should exercise in a certain way because he read it in the book, while his doctor says he should not do that, otherwise he might get a heart attack, then he is not doing the right thing. The doctor is an expert in his field and says that the book does not apply to this person. A person should be guided by people that are greater than him, rather than thinking he is the smartest person in the world.”
[The two opinions cited by the Mechaber in 306 disagree over whether it is allowed to accept pay for chazzanus, but even the lenient opinion agrees that no siman bracha will come from it. It seems that Rav Aharon had two reasons for what he said: Firstly, the Mishnah Berurah says that the custom is to be lenient, and presumably that means that there will be siman bracha as well. Secondly, the Rema says that it is permitted (and presumably there will be siman bracha too) if one includes weekday work with Shabbos. Practicing with the choir was considered weekday work.
Perhaps the young man was hesitant to follow this psak because he thought that the choir practice was not independent work, but merely a preparation for Shabbos. Rav Aharon therefore assured him that because of his circumstances, he should not be strict, but rather accept the opportunity sent to him by Hashem.]
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