Boyd’s Bible Dictionary:

(set on fire). A mixture of gums, spices (Ex. 30:34-38), constituted the official incense. Burned morning and evening on the altar of incense (Ex. 30:1-10). Used also in idolatrous worship (2 Chron. 34:25; Jer. 11:12-17), and by angels (Rev. 8:3).

Concise Bible Dictionary:

Precise instructions were given as to how the sweet incense was to be made that was burnt in the tabernacle. It was a compound of sweet spices: stacte, onycha, galbanum, and pure frankincense, an equal weight of each. It was to be compounded after the art of the apothecary, tempered together (or salted, margin), pure, and holy. No one was to make any like it for their private use: anyone who did so was to be cut off from God’s people (Ex. 30:34-38). This incense was to be burnt on the golden altar morning and evening: “a perpetual incense before the Lord” (Ex. 30:7-8). It expressed the fragrance of the perfections of Christ’s person for God’s delight. It also characterized the worship of the priestly company of those in the light, as Christians are.
The incense was also to be put on burning coals in a censer and carried by the high priest into the most holy place on the Day of Atonement, that the cloud of incense might cover the mercy seat that was upon the testimony, “that he die not.” It typified the personal perfection of Him who carried in the blood of atonement (Lev. 16:12-13). We find that while the high places remained, incense was burnt there as well as sacrifices offered (1 Kings 22:43, and more). The burning of incense to Baal and other false gods is also often spoken of (Jer. 1:16; Jer. 7:9, and more). Satan has his incense and perfume, and makes it a delight to his willing devotees.