Exodus

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.

For Christ is not entered into the holy places made with hands, which are the figures of the true; but into heaven itself, now to appear in the presence of God for us:

In the tabernacle of the congregation without the vail, which is before the testimony, Aaron and his sons shall order it from evening to morning before the Lord: it shall be a statute for ever unto their generations on the behalf of the children of Israel.

According to the custom of the priest’s office, his lot was to burn incense when he went into the temple of the Lord.

And he shall put the incense upon the fire before the Lord, that the cloud of the incense may cover the mercy seat that is upon the testimony, that he die not: