'Thresholds' in the Bible

Shallum the son of Kore, the son of Ebiasaph, the son of Korah, and his relatives of his father’s house, the Korahites, were in charge of the work of the service, doorkeepers of the Tent; and their fathers had been in charge of the camp of the Lord, keepers of the entrance.

All those chosen to be gatekeepers at the thresholds were 212. They were enrolled by their genealogies in their villages [around Jerusalem], these men [whose grandfathers] David and Samuel the seer had appointed to their official duty.