New Revised Standard Version
Thereafter the Levites went in to do their service in the tent of meeting in attendance on Aaron and his sons. As the LORD had commanded Moses concerning the Levites, so they did with them.

Contemporary English Version
After this, the Levites worked at the sacred tent as assistants to Aaron and his sons, just as the LORD had commanded.

New American Bible
Only then did they enter upon their service in the tent of meeting under the supervision of Aaron and his sons. Exactly as the LORD had commanded Moses concerning the Levites, so it was done with regard to them.

Douay-Rheims Bible
That being purified they might go into the tabernacle of the covenant to do their services before Aaron and his sons. As the Lord had commanded Moses touching the Levites, so was it done.

That being purified they might go into the tabernacle of the covenant to do their services before Aaron and his sons. As the Lord had commanded Moses touching the Levites, so was it done.

after that

Numbers 8:15 And afterwards they shall enter into the tabernacle of the covenant, to serve me. And thus shalt thou purify and consecrate them for an oblation of the Lord: for as a gift they were given me by the children of Israel.

2 Chronicles 30:15-17,27 And they immolated the phase on the fourteenth day of the second month. And the priests and the Levites being at length sanctified offered holocausts in the house of the Lord. . . .

2 Chronicles 31:2 And Ezechias appointed companies of the priests, and the Levites, by their courses, every man in his own office, to wit, both of the priests, and of the Levites, for holocausts, and for peace offerings, to minister, and to praise, and to sing in the gates of the camp of the Lord.

2 Chronicles 35:8-15 And his princes willingly offered what they had vowed, both to the people and to the priests and the Levites. Moreover Helcias, and Zacharias, and Jahiel rulers of the house of the Lord, gave to the priests to keep the phase two thousand six hundred small cattle, and three hundred oxen. . . .

as the Lord

Numbers 8:5 And the Lord spoke to Moses, saying: