וּסְבִיב֥וֹת בֵּית־הָאֱלֹהִ֖ים יָלִ֑ינוּ כִּֽי־עֲלֵיהֶ֣ם מִשְׁמֶ֔רֶת וְהֵ֥ם עַל־הַמַּפְתֵּ֖חַ וְלַבֹּ֥קֶר לַבֹּֽקֶר׃
And they lodged round about the house of God, because the charge thereof was upon them, and to them pertained the opening thereof morning by morning.
Read midrashic interpretation of I Chronicles 9:27: and classical rabbinic exegesis.