2 Chronicles 23:6-7

6But let no one enter into the House of Adonai except the kohanim and the ministering Levites. They may come in, for they are kadosh, and let all the people observe the service of Adonai.

7The Levites will surround the king on all sides, every man with his weapons in his hand, and whoever enters the House, let him be killed. Stay close to the king in his comings and goings.”