Carl Friedrich Keil and Franz Delitzsch Old Testament Commentary

After he had made atonement for the dwelling, Aaron was to expiate the altar in the court, by first of all putting some of the blood of the bullock and he-goat upon the horns of the altar, and then sprinkling it seven times with his finger, and thus cleansing and sanctifying it from the uncleannesses of the children of Israel. The application of blood to the horns of the altar was intended to expiate the sins of the priests as well as those of the nation; just as in the case of ordinary sin-offerings it expiated the sins of individual members of the nation (Lev 4:25, Lev 4:30, Lev 4:34), to which the priests also belonged; and the sevenfold sprinkling effected the purification of the place of sacrifice from the uncleannesses of the congregation. The meaning of the sprinkling of blood upon the capporeth and the horns of the two altars was the same as in the case of every sin-offering. The peculiar features in the expiatory ritual of the day of atonement were the following. In the first place, the blood of both sacrifices was taken not merely into the holy place, but into the most holy, and sprinkled directly upon the throne of God. This was done to show that the true atonement could only take place before the throne of God Himself, and that the sinner was only then truly reconciled to God, and placed in the full and living fellowship of peace with God, when he could come directly to the throne of God, and not merely to the place where, although the Lord indeed manifested His grace to him, He was still separated from him by a curtain. In this respect, therefore, the bringing of the blood of atonement into the most holy place had a prophetic signification, and was a predictive sign that the curtain, which then separated Israel from its God, would one day be removed, and that with the entrance of the full and eternal atonement free access would be opened to the throne of the Lord. The second peculiarity in this act of atonement was the sprinkling of the blood seven times upon the holy places, the floor of the holy of holies and holy place, and the altar of the court; also the application of blood to the media of atonement in the three divisions of the tabernacle, for the cleansing of the holy places from the uncleanness of the children of Israel. As this uncleanness cannot be regarded as consisting of physical defilement, but simply as the ideal effluence of their sins, which had been transferred to the objects in question; so, on the other hand, the cleansing of the holy places can only be understood as consisting in an ideal transference of the influence of the atoning blood to the inanimate objects which had been defiled by sin. If the way in which the sacrificial blood, regarded as the expiation of souls, produced its cleansing effects was, that by virtue thereof the sin was covered over, whilst the sinner was reconciled to God and received forgiveness of sin and the means of sanctification, we must regard the sin-destroying virtue of the blood as working in the same way also upon the objects defiled by sin, namely, that powers were transferred to them which removed the effects proceeding from sin, and in this way wiped out the uncleanness of the children of Israel that was in them. This communication of purifying powers to the holy things was represented by the sprinkling of the atoning blood upon and against them, and indeed by their being sprinkled seven times, to set forth the communication as raised to an efficiency corresponding to its purpose, and to impress upon it the stamp of a divine act through the number seven, which was sanctified by the work of God in creation.