(ויתד תהיה לך על אזנך (דברים כ"ג: י"ד
In the times of the second Bais Hamikdash, there were various different kinds of sects and cults in the Jewish community. One of the cults were the ”Issi’im” whom Chazal called “Tovlei Shachris”.(went to the Mikveh every morning). This cult didn’t survive because they never got married.
They were a very interesting cult. They considered Tahara and hygiene as one and were very strict about it. They went to the Mikveh several times a day. They went to the Mikveh before the meals, after relieving themselves and if they touched someone who was from a lower cast of the four groups. They claimed to have prophecy because of the holy lifestyle they followed.
It took a few years to join the cult. There were four groups a) children b) first year in training c) additional two years training d) full fledged members. Once one graduated to full member status they presented him with white clothing, an apron to cover themselves when relieving and a shovel to cover it up in the ground.
They had many Chumros in Hilchos Shabbos. They held that all utensils even a כלי שמלאכתו להיתר are Muktzah. Shovels which are מלאכתו לאיסור was for sure Muktza even when used לצורך גופו . They would not use the washroom the whole Shabbos because they couldn’t use the shovel.
Now that you know this piece of history you will understand the Gaon on the last Tosefta in Meseches Yodayim ועיין שם