Leviticus 16:13

“And he shall put the incense upon the fire before the Lord, etc.] Both the incense and burning coals of fire being carried within the vail, the incense was put upon the coals, and so it burned before the Lord, whose seat was between the cherubim; and from whence it appears, that this was done, not without but within the vail: the Sadducees under the second temple would have it, that the incense was put upon the fire without the vail, wherefore the high priest, on the evening of this day, was sworn by the messengers of the sanhedrim not to make any alteration in what they should say to him; and this oath was given him in the house of Abtines, where the incense was made, with a special respect…”

“It is important, in reference to the meaning of the day of atonement, to observe the order of the rites as they are described in these verses. Leviticus 16:12 A censer - See Exodus 25:38 note. The altar before the Lord - i. e. the altar of burnt-offering on which the fire was always burning. Leviticus 16:14 The high priest must have come out from the most holy place to fetch the blood, leaving the censer smoking within, and then have entered again within the veil. He sprinkled the blood seven times upon the mercy-seat, on its east side (not “eastward”), and then seven times upon the floor in front of it. If the mercy-seat may be regarded as an altar, the holiest one of the three, on this one…”

“Upon the fire - Which was in the censer, Lev 16:12. Leviticus 16:14”

“And he: Exo 30:1, Exo 30:7, Exo 30:8; Num 16:7, Num 16:18, Num 16:46; Rev 8:3, Rev 8:4 the cloud: Exo 25:21; Heb 4:14-16, Heb 7:25, Heb 9:24; Jo1 2:1, Jo1 2:2 Leviticus 16:14”