One of the most frequently invoked and familiar themes of our mesorah is that kol yisroel yesh lachem chelek b’Olam Habah. However, as we also know, not all “shares” are equal. Its easy to say that a especially heilege tzadik will have a greater “share” than a poishete yid or that one could easily “lose his/her share” by engaging in evil and failing to do real tshuvah.
Against that framework, one can bring down many statements from chazal that performing a particular mitzvah/chumrah will “guarantee” a person’s chelek and vice versa, a particularly egregious aveirah will result in the permanent loss of that chelek.
This type of hyperbole is certainly is not a consensus view nor do the majority of gadolim subscribe to a goiyeshe-styled notion that yidden can “earn our way into Heaven” by performing a prescribed set of mitzvot or overlaying chumrah upon chumrah. We perform the mitzvot because it is our “privilege” and “obligation” and out of a sense of ahavas hashem and not to accrue sufficient “mitzvah credits” like frequent flyer miles to secure our chelek of olam haboh.