Exodus 30:21

21 it shall be a lawful thing everlasting to him and to his seed by successions. (this shall be an everlasting law for him and for his descendants by succession.)

Exodus 30:21 Meaning and Commentary

Exodus 30:21

So they shall wash their hands and their feet, that they
die not
By the immediate hand of God, who would so greatly resent such a neglect of his command; and by how much easier it was to perform it, by so much the more were they inexcusable, and to be treated with greater severity; and this is repeated, that they might carefully observe it, lest they perish:

and it shall be a statute for ever to them, [even] to him and to
his seed, throughout their generations;
to be observed by Aaron and his descendants in all ages, as long as their priesthood lasted, until the Messiah should come, and wash all his people, his priests, with his own blood, from all their sins, ( Revelation 1:5 Revelation 1:6 ) .

Exodus 30:21 In-Context

19 Aaron and his sons shall wash therein their hands and their feet,

20 when they shall enter into the tabernacle of witnessing, and when they shall nigh to the altar, that they offer therein incense to the Lord, lest peradventure they die; (whenever they shall go into the Tabernacle of the Witnessing, or when they shall approach the altar to offer incense on it to the Lord, otherwise they shall die/or they shall be killed;)

21 it shall be a lawful thing everlasting to him and to his seed by successions. (this shall be an everlasting law for him and for his descendants by succession.)

22 And the Lord spake to Moses, and said,

23 Take to thee sweet smelling spiceries, of the first and chosen myrrh, (equal to the weight of) five hundred shekels; and of canel the half (and half as much canel), that is, (the weight of) two hundred and fifty shekels; [and] in like manner of calamus, that is, a sweet smelling tree, small and full of knots, (the weight of) two hundred and fifty shekels;