Exodus 30:6-9

You shall put this altar in front of the veil that is near the ark of the testimony, in front of the mercy seat that is over the ark of the testimony, where I will meet with you. Aaron shall burn fragrant incense on it; he shall burn it every morning when he trims the lamps. When Aaron trims the lamps at twilight, he shall burn incense. There shall be perpetual incense before the LORD throughout your generations. You shall not offer any strange incense on this altar, or burnt offering or meal offering; and you shall not pour out a drink offering on it.