One may not eat a korban when he is ritually impure. Blood and cheilev, forbidden animal fats, are prohibited to eat. Aharon and his sons are granted the breast and shank of every korban shlamim. The inauguration ceremony for Aharon, his sons, the Mishkan and all of its vessels is detailed. Because our society lacks a true spiritual center, the only quality that is prized is revelation.
Revelation is all.
That which is unseen or cannot be seen is distrusted and disregarded. Holiness is something which has to be covered. Its very nature requires covering. At any time there exist 36 holy people on whose merit the whole world rests. They are hidden.