“which had the golden censer and the ark of the covenant overlaid on all sides with gold, in which were the golden pot that had the manna, Aaron’s rod that budded, and the tablets of the covenant” (Hebrews 9:4).
Although the Scriptures do not provide us with a description of the golden censer mentioned here in Hebrews 9:4, the Old Testament book of Leviticus offers a look at its function…
“The Lord said to Moses: ‘Tell your brother Aaron that he is not to come whenever he chooses into the Most Holy Place behind the curtain in front of the atonement cover on the ark, or else he will die. For I will appear in the cloud over the atonement cover…
He is to take a censer full of burning coals from the altar before the Lord and two handfuls of finely ground fragrant incense and take them behind the curtain. He is to put the incense on the fire before the Lord, and the smoke of the incense will conceal the atonement cover above the tablets of the covenant law, so that he will not die'” (Leviticus 16:2, 12-13 NIV).
So, this cloud of fragrant incense shielded the officiating priest from a direct view of the almighty God on the Day of Atonement. We find the reason behind that precautionary measure in Exodus 33:20: “…you may not look directly at my face, for no one may see me and live” (NIV).
Nevertheless, there seems to be a question of whether the original language of this passage actually refers to the Tabernacle’s altar of incense. This altar stood outside the Most Holy Place according to Exodus 30:6 and not within it as we read here in Hebrews 9:4. If this passage is meant to refer to this altar, then we have several options available to reconcile this seeming inconsistency.
One approach views the altar of incense as an appendage of the Holy Place. This would be comparable to the exterior signage of a business. Even though a sign is located outside the building or storefront, it belongs to the business and not the street. (1) However, the best explanation is probably offered by the following commentary…
“Verse 4 says that the golden censer was also in the Most Holy Place. The Greek word translated censer can mean either the incense altar (mentioned in Exo 30:6 as being in the Holy Place) or the censer with which the high priest carried the incense. The best explanation is the latter. The writer regarded the censer as belonging to the Most Holy Place because the high priest carried it in from the incense altar into the Holiest Place on the Day of Atonement.” (2)
(1) See Coffman, James Burton. “Commentary on Hebrews 9”. “Coffman’s Commentaries on the Bible”. https://www.studylight.org/commentaries/eng/bcc/hebrews-9.html. Abilene Christian University Press, Abilene, Texas, USA. 1983-1999.
(2) William Macdonald, Believer’s Bible Commentary Edited by Arthur Farstad Thomas Nelson Publishers (2 Corinthians 5:10) p.2261