Buried Alive

מסכת שמחות ריש פרק ח

יוצאין לבית הקברות ופוקדין כל המתים עד שלשים יום, ואין חוששין משום דרכי האמורי. ומעשה שפקדו אחד אחר שלשים יום, וחיה עשרים וחמש שנים ואחר כך מת, ואחר הוליד חמשה בנים ואחר כך מת.

Masechet Semachot Ch. 8

One may go to the cemetery and check up on the deceased 30 days after burial, and we are not concerned that this practice stems from non-Jewish customs. They once checked up on a dead guy 30 days after they buried him, [found him to be alive,] and he lived for another 25 years. There was another guy who fathered five children.

In the 18th century, a government in Europe tried to pass legislation that would delay the burial of a deceased person for a few days to confirm that he is indeed as dead as a doorknob. Moses Mendelssohn tried to use this berayta as a proof that this claim is, in fact, a legitimate one and that the European law should be observed as a measure of pikuach nefesh. The Chattam Sofer and others argued that even though one or two incidents have indeed occurred, they are not definitive enough to require us to disregard the halacha that instructs us to inter the deceased immediately. (The teshuvot can be found in the Pitchei Teshuva Y"D 357:1)