In this response, we assume that the father is following a legitimate opinion and that the family is not bound by a local ruling. We can address only a few principles and applications.
The topic begins with a gemara.[1] The people of Beishan had the practice not to travel to Tzidon on Fridays. Their sons approached Rabbi Yochanan, hoping to end this practice, which they found difficult. Rabbi Yochanan said that since their fathers had already accepted the stringency, the pasuk “… do not forsake your mother’s Torah”[2] applied, and they had to continue the practice.
The Rivash,[3] Chavot Yair[4] and others say that the fathers of Beishan did not have the authority to obligate their sons individually, but, as a community, they could create a minhag hamakom (local practice). The Chavot Yair reasons that people raised in Beishan who moved elsewhere could have ceased keeping the minhag, whereas newcomers to Beishan were obligated by it. The Zichron Yosef[5] makes the following distinction. A stringency that a father accepts is binding on his son only if the son began keeping the minhag, which was the situation in Beishan. Of what significance, then, was the fathers’ acceptance, if the sons were, anyway, bound by their own actions? The Korban Netanel[6] cites an opinion that states that since the minhag stemmed from the fathers’ acceptance, it was not possible to stop the practice by using hatarat nedarim (absolution of oaths). Other answers are given, as well.
We have discussed cases where a father accepted stringencies that exceeded halachic requirements. Do the same rules apply to our case in which the father’s practice follows one side of a machloket concerning whether something is objectively permitted or forbidden? Recent poskim discuss a parallel case that includes both types of practices – a marriage between an Ashkenazi and a Sephardi who are unsure whose practice they should adopt on matters where there is no established local practice in their community. (The question was rare centuries ago because couples followed the minhagim and rulings of the place they lived; now, most cities have separate communities based on edah (ethnic subgroup)). The Tashbetz[7] and most recent poskim,[8] who say that the wife adopts the practices of her husband’s edah, make little or no distinction between minhag and halachic rulings.
Is the wife’s following of her husband’s practices a valid precedent for children living at home? We cannot delve into a full explanation, but it appears that the level of interconnectedness, the potential for conflict, and the prospect of staying under one roof for many decades are issues that are qualitatively more significant for spouses than for children. Thus, one cannot conclude that children are automatically “drawn after” their father’s practices. On the other hand, numerous sources assume that children follow their father’s lead under normal circumstances, even in the absence of a community-wide practice. For example, the Maharam Shick[9] says that the fact that a young adult living with his father refrains from the same things as his father is not a sign that he has accepted these practices indefinitely. Actually, one is expected to conform when possible, for leniency or stringency, even to the halachic practices of one’s unrelated host in order to avoid acrimony. This is all the more so regarding a father, who not only links the child to the chain of tradition, but whom the child is obligated to honor. Yet, there are times that children may act differently from their father even in his presence.[10] Much depends on the father’s tolerance and other circumstances.[11]
In summary, a father’s practice need not determine halachic rulings for his child who is mature enough to choose his own path. However, his approach is the assumed point of departure, and his feelings should be considered, especially in his presence.