Numbers 18 - In this chapter it is made very explicit that for all times only the Levites are to do service at the tent of meeting and of the Levites only those of Aaron’s family are to be priests of the sanctuary.  Out of the offerings and sacrifices established the Levites shall be entitled to the meat. 

They are also entitled to every first-born male but he is to be ransomed by payment of five shekels of silver.  The Levites are entitled to this tithe because of their service to the Lord and because the work of service will prevent them from having a share in the Promised Land.  And out of all the tithes contributed by the people, the house of Aaron will be entitled to a tithe of the tithes. 

The Lord calls the arrangement he makes with the tribe of Levi and “inviolable covenant to last forever before the Lord, for you and for your descendants” (18:19). Schocken editors translate it a “covenant of salt” because salt prevents decay. So we see the entire religious establishment assigned its duties and stations and the whole placed at the center of Israeli life and culture, both physically and economically the Levites are at the center of the community for in a very real sense they are responsible for holding it together and holding it under the protection of the Lord.

Irenaeus of Lyons (c.180 AD)

Selections from the Work Against Heresies

Book V – Redemption and the World to Come

The New Creation in Christ “Recapitulates” the Old

Some Glimpses of Irenaeus’ Teaching on the Last Things

33 – It is “[b]ecause of this, when he came to his Passion, that he might declare to Abraham and those with him the glad tidings of the opening of the inheritance, after ha had given thanks as he held the cup, and had drunk of it, and given to the disciples, he said to them: ‘Drink of this, all of you. For this is my blood of the new covenant, which is shed for many for the remission of sins. For I say to you that I will not drink of the produce of the vine, until that day when I shall drink it with you new in the Kingdom of my Father.’”

There will be “hundredfold” rewards for the faithful in the “times of the Kingdom, that is, on the seventh day, which is sanctified, in which, in which God rested from all his works which he made; this is the true Sabbath of the just, in which they will have no earthly work to do, but will have a table prepared before them by God, who will feed them with dainties of all kinds.”

Just like references to the Promised Land to Abraham, later promises to Isaac and Jacob, also are metaphorical and relate primarily to the ultimate restoration of all the earth to God’s original plan. When Isaac blesses his son Jacob, he says “’Behold the smell of my son is as the smell of a rich field, which God has blessed.’ The field [here referred to] is the world—and therefore he added: ‘God give you of the dew of heaven, and of the fertility of the earth, abundance of grain and of wine. And the nations will serve you, and princes will worship you, and you will be Lord over your brother, and the sons of your father will worship you. . . If one does not take this as referring to the destined [times] of the Kingdom, he finds himself in great contradiction and confusion . . . For not only did the nations not serve Jacob in his life, but he, when he set forth after this blessing, served his uncle Laban the Syrian for twenty years. Not only was he not made lord of his brother, but he himself worshiped Esau his brother, when he came back from Mesopotamia to his father and offered many gifts to him.”