Hebrews 5:4

"And take thou unto thee Aaron thy brother, and his sons with him, from among the children of Israel, that he may minister unto me in the priest's office, even Aaron, Nadab and Abihu, Eleazar and Ithamar, Aaron's sons."

"And he spake unto Korah and unto all his company, saying, Even to morrow the LORD will shew who are his, and who is holy; and will cause him to come near unto him: even him whom he hath chosen will he cause to come near unto him."

"To be a memorial unto the children of Israel, that no stranger, which is not of the seed of Aaron, come near to offer incense before the LORD; that he be not as Korah, and as his company: as the LORD said to him by the hand of Moses."

"And they withstood Uzziah the king, and said unto him, It appertaineth not unto thee, Uzziah, to burn incense unto the LORD, but to the priests the sons of Aaron, that are consecrated to burn incense: go out of the sanctuary; for thou hast trespassed; neither shall it be for thine honour from the LORD God."

"The sons of Amram; Aaron and Moses: and Aaron was separated, that he should sanctify the most holy things, he and his sons for ever, to burn incense before the LORD, to minister unto him, and to bless in his name for ever."

"Therefore thou and thy sons with thee shall keep your priest's office for every thing of the altar, and within the vail; and ye shall serve: I have given your priest's office unto you as a service of gift: and the stranger that cometh nigh shall be put to death."

"And there came out a fire from the LORD, and consumed the two hundred and fifty men that offered incense."

"John answered and said, A man can receive nothing, except it be given him from heaven."