Halakhah do Wyjścia 30:31

The commandment of anointing the high priest and the kings of the House of David with anointing oil: To make the anointing oil according to the way that the Torah commanded to make it, as it is stated (Exodus 30:25), "And you shall make it, a holy anointing oil, etc." [This is] so that it be ready to anoint every high priest that is appointed, as it is written (Leviticus 21:10), "The priest who is exalted above his fellows, on whose head the anointing oil has been poured." And so [too], we anoint some of the kings. And so [too,] they also anointed the vessels of the Temple with it, but they will not need to anoint [them] in the future, as they will be sanctified by their service. And this is [the meaning] of what is written (Exodus 30:31), "and it will be for Me for the generations." And so did they, may their memory be blessed, say in Sifrei Bemidbar 44.