LXX Num 1:53

δὲ Λευεῖται παρεμβαλέτωσαν ἐναντίον Κυρίου κύκλῳ τῆς σκηνῆς τοῦ μαρτυρίου, καὶ οὐκ ἔσται ἁμάρτημα ἐν υἱοῖς Ἰσραήλ. καὶ φυλάξουσιν οἱ Λευεῖται αὐτοὶ τὴν φυλακὴν τῆς σκηνῆς τοῦ μαρτυρίου.

But the Levites are to camp around the tabernacle of the Testimony and watch over it, so that no wrath will fall on the congregation of Israel. So the Levites are responsible for the tabernacle of the Testimony.”