Melachim Bais 11:5-7

Orthodox Jewish Bible

⁵ And he commanded them, saying, This is the thing that ye shall do; a third part of you that come on duty on Shabbos shall even be Shomrei Mishmeret Bais HaMelech (Guards on duty at the Royal Palace);

⁶ And a third part shall be at the Sha’ar Sur; and a third part at the Sha’ar behind the ones guarding: so shall ye keep shomer the mishmeret HaBais for defense.

⁷ And two companies of all you that go off duty on Shabbos, even they shall keep shomer the mishmeret Beis Hashem for HaMelech.