Chapter 4 of Massechet Pesachim is called מקום שנהגו (“In a place where it is the custom to…”), and it is here where many of the rules pertaining to מנהגים (customs) are derived. For example, in yesterday’s daf (Pesachim 50b) we were taught that once a custom has been adopted by a community, it then becomes binding on later generations. Similarly, as we learn in today’s daf (Pesachim 51a), if someone travels to a community who have adopted a particular custom, it is necessary to adhere to such customs.
Given all this, the Shulchan Aruch (Yoreh Deah 214:2) rules that, “when a large number of people adopt a custom, this [custom] falls on them and their descendants. This applies even when the people did not accept this custom explicitly, but instead, accustomed themselves to follow it as a ‘fence’ to avoid transgressing Torah laws. Similarly, when people come from outside the city to live there, they become residents of the city and are obligated to act in accordance with the customs that have been instituted. And even in cases where custom forbade them to act in a certain way in their old city, and this is not the custom in their new city, it becomes permitted for them as long as they do not intend to return [to their old city].”
In light of this ruling, the Pitchei Teshuva (YD 214 note 5) clarifies that a child is only required to follow the customs of their father in a situation where they have been taught those customs and “it is this type of case that the Mechaber (Rabbi Yosef Karo) addresses when writing that ‘when a large number of people adopt a custom, this [custom] falls on them and their descendants’ i.e. this case is where the residents of the city and their descendants have already practiced this custom”. However, in a situation where the child never followed the customs of their father, they are not bound to adopt these customs.
This ruling has significant implications for the contemporary era, and in response to a question about whether someone who is a Ba’al/Ba’alat Teshuva must adopt the Chassidic customs which their father had previously observed in his youth but who had since strayed from religion prior to getting married, Rabbi Moshe Sternbuch (Teshuvot VeHanhagot 1:354) quotes this ruling of the Pitchei Teshuva and then explains – based on the ideas found in today’s daf – that customs are not solely parent-dependent, but are, instead, also place and community dependent, and that they only take effect if they have been passed on. In light of this, if a Ba’al/Ba’alat Teshuva has not been raised with specific customs from their home, and has, instead, found a spiritual community or spiritual guides who have inspired them, then it is permitted – according to the notion of מקום שנהגו – to adopt the customs of these spiritual guides or of the spiritual community where they now belong. In this same spirit and as noted by Rabbi Shlomo Zalman Auerbach (Halichot Shlomo: Tefillah Ch. 5 note 80) and others, a convert is not obligated to adopt the customs of their country of origin.
Ultimately, a close look at this topic leads us to the conclusion that customs come from many different places, and that just as someone who travels to a community should adopt the customs of their new location, so too, someone who has not been passed on specific customs from their parents may adopt the customs of their new spiritual community.