And he burnt sweet incense thereon
Which is another branch of the priestly office exercised by Moses, and which he would never have done had he not had a command from God for it, as follows:
as the Lord commanded Moses;
he commanded Moses indeed to order and direct Aaron to do this, but he being not yet consecrated, Moses, being the Lord's priest, did it.
The Brenton translation of the Septuagint is in the public domain.