גדר מנהג מבטל הלכה

We have shown previously in this series that even though there is no fully legitimate reason not to do ברכת כהנים daily in חו"ל (or anywhere for that matter) - still, those who attempted to do so were stopped from Heaven. The question begs itself to be asked: why would great people be stopped by Heaven from doing what הלכה demands of them?

Some have suggested that perhaps this was not the right thing to do in the first place: after all, there is a principle that מנהג מבטל הלכה. -?-

In this article we will address where the aforementioned principle applies or doesn't apply, and, in the process, we will see whether it applies here or not.

1

To begin with, a Sefaria search indicates that the overwhelming majority of halachic sources that apply this principle - do so in relation to monetary matters, which are beyond the purview of this forum. This would indicate, however, that monetary matters are the primary area in which מנהג is מבטל הלכה to begin with. There are only a handful of instances where מנהג מבטל הלכה comes up in the halachic literature relating to איסור והתר. We will delineate each of them here, one by one.

2

One of the earliest sources to mention מנהג מבטל הלכה is מסכת סופרים [1], where this principle is immediately qualified by saying that "a מנהג which can be מבטל הלכה is only such a מנהג that was established by ותיקים; but a מנהג that has no proof from the תורה is not a מנהג but rather a mistake in judgment". This qualification is also codified as פסק הלכה by the מהריק (see here).

3

A full treatment of the issue is beyond the scope of this article, but אבודרהם [2] has a discussion whether or not to say ברוך ה לעולם between שומר עמו ישראל לעד and חצי קדיש in a weeknight מעריב, due to a concern of needing to juxtapose גאולה to תפלה, and ברוך ה לעולם being an interruption thereto. He concludes that "our ancestors have already accustomed themselves to saying it - and their מנהג is תורה - as we say that מנהג is מבטל הלכה".

One must observe, however, that halachic justification is offered there to do so, in that ברוך ה לעולם is תפלה, by virtue of its containing many theoretical components of שמונה עשרה. Indeed, this reasoning seems to have been adopted universally among אשכנזים (with the notable exception of the גרא and - ironically - the בעל התניא who deleted it from their respective סדורים).

4

The מאירי [3] says that מנהג is only מבטל הלכה where הלכה is מקיל and מנהג is מחמיר, or where מנהג is מקיל where there is no איסור; but if a מנהג is מקיל where there is an איסור - we don't listen to the מנהג.

Conclusion

מנהג מבטל הלכה is a halachic principle that, like many halachic principles, is not a blanket statement - that מנהג is ALWAYS מבטל הלכה - but rather, applies in some places and not in others - as in מנהג is sometimes מבטל הלכה.

Where, indeed, מנהג is מבטל הלכה is 1) in (some) monetary matters  - the details of where it does or not in this regard being beyond the scope of this forum, 2) for איסור והתר - where established by ותיקים and - where there is a מחלוקת as to what the הלכה should be, or the מנהג is more מחמיר than the strict הלכה, or where מנהג is מקיל שלא במקום איסור [4].

In addition to all that has been said so far, none of the classical פוסקים, in discussing this סוגיא, invoke מנהג מבטל הלכה at all. I would be hesitant to apply a halachic principle to a particular situation where none of the earlier פוסקים have done so.

[1] יד:יח

[2] סדר התפלות לחול - ערבית

[3] .ראש השנה טז

[4] Not to do ברכת כהנים every day is not a קולא but rather a חומרא: the פוסקים who offer reasons why not to - for example, the כהנים cannot טובל, or they are not מיוחס, or we are not happy enough, or it is a טורח הציבור that causes people to lose work etc., - all offer reasons for an איסור rather than a פטור.