Changing customs from a Holy place to a non-Holy place

Question

The mishnah in Pesachim (4:1) says:

הַהוֹלֵךְ מִמְּקוֹם שֶׁעוֹשִׂין לִמְקוֹם שֶׁאֵין עוֹשִׂין, אוֹ מִמְּקוֹם שֶׁאֵין עוֹשִׂין לִמְקוֹם שֶׁעוֹשִׂין, נוֹתְנִין עָלָיו חֻמְרֵי מָקוֹם שֶׁיָּצָא מִשָּׁם וְחֻמְרֵי מָקוֹם שֶׁהָלַךְ לְשָׁם. וְאַל יְשַׁנֶּה אָדָם, מִפְּנֵי הַמַּחֲלֹקֶת:

One who goes from a place where they do [work], to a place where they do not do [work], or from a place where they do not do [work] to a place where they do [work], we place upon him the stringencies of the place he came from, [or] the stringencies of the place that he went to. And a man should not deviate [from the established customs of a place], on account of [the] disagreement [to which such conduct may lead].

We see from here that a person should go with the common custom of the place they've traveled to, so long as it doesn't lead to a leniency.

Unfortunately I don't have much to go with. Someone told me that there is an idea somewhere, he believes in the gemarra, that this doesn't apply if going from a Holy place/מקום קדוש to a non Holy place/מקום שאינו קדוש. I guess an example would be from Eretz Yisroel to Chutz LaAretz. This doesn't seem correct to me, but he was quoting someone reputable, so I assume someone says it...somewhere. Even if it's not halacha lema'aseh...:-) Where can I find such an idea?

Answer 1

Perhaps you are looking for this Gemara in Chulin 18b.

Here is the key quote from Sefaria.org (with their elaboration) (but the surrounding Gemara is relevant as well):

The Gemara asks: And does Rabbi Zeira not accept the principle that when a person travels from place to place, the Sages impose upon him the stringencies of the place from which he emerged and the stringencies of the place to which he went?

Abaye said: That statement applies when one travels from one place in Babylonia to another place in Babylonia, or from one place in Eretz Yisrael to another place in Eretz Yisrael, or alternatively, when one descends from Eretz Yisrael to Babylonia. But when one ascends from Babylonia to Eretz Yisrael, this principle does not apply. Since we, the residents of Babylonia, are subordinate to them in terms of halakha, we act in accordance with their custom.

Rav Ashi said: Even if you say that when one travels from Babylonia to Eretz Yisrael, he is required to act stringently in accordance with the custom of the place from which he emerged, that statement applies only in a case where his intent is to return. Rabbi Zeira was not one whose intent was to return. Therefore, he was not obligated to observe the Babylonian stringencies.