At the beginning of the modern times it was traditional to present biblical tales as a play to the people. Most of the population was not able to read or write, because of this circumstances they had to play religious events like Christmas and Eastern to bring the celebrations closer to the people. “Grabstehen” ( to watch about Jesus`grave) is an oddment of that time.
The marksmen (“Schützen“) took this tradition from a sacrament-brothership.
“Grabstehen” ist one of the heights of the season. Another one is the “Prangertag” at Feast of Corpus Christi (“Fronleichnam”).