Numbers 18:19

19 Whatever is set aside from the holy offerings the Israelites present to the LORD I give to you and your sons and daughters as your perpetual share. It is an everlasting covenant of salt before the LORD for both you and your offspring.”

Read Numbers 18:19 Using Other Translations

All the heave offerings of the holy things, which the children of Israel offer unto the LORD, have I given thee, and thy sons and thy daughters with thee, by a statute for ever: it is a covenant of salt for ever before the LORD unto thee and to thy seed with thee.
All the holy contributions that the people of Israel present to the LORD I give to you, and to your sons and daughters with you, as a perpetual due. It is a covenant of salt forever before the LORD for you and for your offspring with you."
Yes, I am giving you all these holy offerings that the people of Israel bring to the LORD . They are for you and your sons and daughters, to be eaten as your permanent share. This is an eternal and unbreakable covenant between the LORD and you, and it also applies to your descendants.”

What does Numbers 18:19 mean?

John Gill's Exposition of the Bible
Numbers 18:19

All the heave offerings of the holy things
All before mentioned, and whatsoever comes under that name:

which the children of Israel offer unto the Lord;
either by his commandment, or of their own freewill;

have I given thee, and thy sons, and thy daughters with thee, by a
statute for ever:
so providing for their maintenance by an irrepealable law as long as their priesthood lasted, even until the Messiah should come:

it [is] a covenant of salt for ever before the Lord unto thee, and thy
seed with thee:
an incorruptible, inviolable, durable covenant, which should last for ever, even until the Gospel dispensation or world to come should take place; and it would remain ever before the Lord in his sight, who would take care it should never be made void, but stand fast with Aaron and his posterity as long as his priesthood endured.

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