2 Chronicles 23:6-7

6But let none come into the house of Jehovah except the priests and those of the Levites that do the service; they shall go in, for they are holy; but all the people shall keep the watch of Jehovah.

7And the Levites shall encompass the king round about, every man with his weapons in his hand; and he that comes into the house shall be put to death; and ye shall be with the king when he comes in and when he goes out.