this shabbos is shabbos (duh) yom kippur, which is called shabbos shabboson, and in a shmittah year, which is also called shabbos. Is there any significance to this, and when was the last time this happened?
No idea but I hope it brings menucha.
shabbos on Yom kippur isnt rare (in fact it is the most likely day though not by far) it occurs slightly less than 1/3 of the time. Shemitah as You know is one in 7 years so about every 3-4 shemitah or 21-28 years you can expect your “3 in 1 Shabbos”
actually, i looked it up after i asked and it happened 7 years ago (last shmittah)
It happens again in 2028, 2035; It also happened 1993 & 2007 as coffee addict already mentioned.