'Service Of The Lord' in the Bible

And Aaron shall offer the Levites before the LORD for an offering of the children of Israel, that they may execute the service of the LORD.

But that it may be a witness between us, and you, and our generations after us, that we might do the service of the LORD before him with our burnt offerings, and with our sacrifices, and with our peace offerings; that your children may not say to our children in time to come, Ye have no part in the LORD.

So all the service of the LORD was prepared the same day, to keep the passover, and to offer burnt offerings upon the altar of the LORD, according to the commandment of king Josiah.