What did the smoke of the incense do in the inner room of the tabernacle?
The smoke of the incense covered the little inner room, literally obliterating the very presence of God from even the high priest. The high priest burned incense on the golden altar, not animal fat, and that smoke shielded or veiled the divine presence as he ministered in that sacred space.
Les explains that especially on the Day of Atonement, the high priest took coals from off the brazen altar and carried them into the little inner altar, where he would burn incense rather than animal fat. The smoke of that incense would literally cover the little room and, as it were, obliterate the very presence of God from even the high priest. Les connects this to Christ's finished work, and notes that the book of Revelation identifies the sweet odor of the incense as the prayers of the saints.