Leviticus 21:23

And thou shalt put it before the vail that is by the ark of the testimony, before the mercy seat that is over the testimony, where I will meet with thee. And Aaron shall burn thereon sweet incense every morning: when he dresseth the lamps, he shall burn incense upon it. And when Aaron lighteth the lamps at even, he shall burn incense upon it, a perpetual incense before the LORD throughout your generations.

And he put the golden altar in the tent of the congregation before the vail:

Thus saith the Lord GOD; No stranger, uncircumcised in heart, nor uncircumcised in flesh, shall enter into my sanctuary, of any stranger that is among the children of Israel. And the Levites that are gone away far from me, when Israel went astray, which went astray away from me after their idols; they shall even bear their iniquity. Yet they shall be ministers in my sanctuary, having charge at the gates of the house, and ministering to the house: they shall slay the burnt offering and the sacrifice for the people, and they shall stand before them to minister unto them. Because they ministered unto them before their idols, and caused the house of Israel to fall into iniquity; therefore have I lifted up mine hand against them, saith the Lord GOD, and they shall bear their iniquity. And they shall not come near unto me, to do the office of a priest unto me, nor to come near to any of my holy things, in the most holy place: but they shall bear their shame, and their abominations which they have committed. But I will make them keepers of the charge of the house, for all the service thereof, and for all that shall be done therein.