Question: "What was the significance of the altar of incense?"
Answer: The altar of incense is first mentioned in Exodus chapter 30 as one of the items inside the Holy Place of the tabernacle. The top of the altar was square—one cubit per side—and the whole altar was two cubits high. A cubit was about twenty inches, or just under two feet. The altar of incense was made of acacia wood and overlaid with gold. It had four “horns,” one at each corner, similar to the altar of sacrifice in the courtyard (Exodus 30:2; cf. 27:2). Rings of gold were built into the altar so that it could be carried with acacia wood poles that were slipped through the rings. The altar of incense was placed before the veil that separated the Holy Place from the Holy of Holies. On the other side of the veil was the Ark of the Testimony, where the presence of God was (Exodus 25:22).
Aaron was instructed to burn incense on the altar each morning and at twilight, every day, as a regular offering to the Lord (Exodus 30:7–8). God gave the recipe for making the incense and stipulated that no other incense ever be burned on the altar (verses 34–38). The fire used to burn the incense was always taken from the altar of burnt offering outside the sanctuary (Leviticus 16:12). Never was the altar of incense to be used for a burnt offering, a grain offering, or a drink offering (Exodus 30:9). Once a year, on the Day of Atonement, the high priest was to put blood on the horns of the altar of incense to cleanse it. The altar of incense was called “most holy to the Lord” (verse 10).
Of course, God’s primary desire for His people is that they be holy. Simply going through the rituals required by the Law—including the burning of incense on the altar of incense—was not enough to make the Israelites right with God. The Lord wanted their hearts and lives to be right, not just their formalities. During Isaiah’s time, the people were disobedient to God, yet they still maintained the temple rites, and that’s why God said through the prophet, “Stop bringing meaningless offerings! Your incense is detestable to me” (Isaiah 1:13). More important than burning the proper incense at the proper time with the proper fire with the proper implements was having a proper heart before God.
In Scripture, incense is often associated with prayer. David prayed, “May my prayer be set before you like incense” (Psalm 141:2). In his vision of heaven, John saw that the elders around the throne “were holding golden bowls full of incense, which are the prayers of God’s people” (Revelation 5:8; cf. 8:3). As Zechariah the priest was offering incense in the temple in Luke 1:10, “all the assembled worshipers were praying outside.”
The altar of incense, then, can be seen as a symbol of the prayers of God’s people. Our prayers ascend to God as the smoke of the incense ascended in the sanctuary. As the incense was burned with fire from the altar of burnt offering, our prayers must be kindled with heaven’s grace. The fact that the incense was always burning means that we should always pray (Luke 18:1; 1 Thessalonians 5:17). The altar of incense was holy to the Lord and was atoned for with the blood of the sacrifice; it is the blood of Christ applied to our hearts that makes our prayers acceptable. Our prayers are holy because of Jesus’ sacrifice, and therefore they are pleasing to God.
The altar of incense can also be seen as a picture of the intercession of Christ. Just as the altar of sacrifice in the courtyard was a type of Christ’s death on our behalf, the altar of incense in the Holy Place was a type of Christ’s mediation on our behalf—Christ’s work on earth and in heaven. The altar of incense was situated before the mercy-seat of the Ark—a picture of our Advocate’s standing in the presence of the Father (Hebrews 7:25; 9:24). The incense was to be burning continually on the altar of incense, which shows the perpetual nature of Christ’s mediation. Christ’s intercession on our behalf is a sweet-smelling savor to God.
It is beautiful to know that God considers the prayers of believers to be like a sweet smell of incense. Because of Christ, we can now enter God’s holy presence by faith, with full assurance (Mark 15:38; Hebrews 4:16). We offer our prayers upon the altar, trusting in Jesus, our eternal, perfect, and faithful High Priest (Hebrews 10:19–23).