“And the priest shall put some of the blood upon the horns of the altar of sweet incense before the LORD.” Leviticus 4:7
The altar of incense is the place where saints present their prayers and praises; and it is delightful to think of it as sprinkled with the blood of the great sacrifice. This it is which makes all our worship acceptable with Jehovah: He sees the blood of His own Son and therefore accepts our homage.
It is well for us to fix our eyes upon the blood of the one offering for sin. Sin mingles even with our holy things, and our best repentance, faith, prayer, and thanksgiving could not be received of God were it not for the merit of the atoning sacrifice. Many sneer at “the blood”; but to us it is the foundation of comfort and hope. That which is on the horns of the altar is meant to be prominently before our eyes when we draw near to God. The blood gives strength to prayer, and hence it is on the altar’s horns. It is “before the Lord”, and therefore it ought to be before us. It is on the altar before we bring the incense; it is there to sanctify our offerings and gifts.
Come, let us pray with confidence, since the Victim is offered, the merit has been pleaded, the blood is within the veil, and the prayers of believers must be sweet unto the Lord.
From "Faith's Checkbook" by Charles H. Spurgeon