'Perpetual Statute' in the Bible

And thou shalt gird them with girdles, Aaron and his sons, and bind head-tires on them: and they shall have the priesthood by a perpetual statute: and thou shalt consecrate Aaron and his sons.

It shall be a perpetual statute throughout your generations in all your dwellings, that ye shall eat neither fat nor blood.

And it shall be for Aaron and his sons; and they shall eat it in a holy place: for it is most holy unto him of the offerings of Jehovah made by fire by a perpetual statute.

And it shall be a perpetual statute unto them: and he that sprinkleth the water for impurity shall wash his clothes, and he that toucheth the water for impurity shall be unclean until even.