10123. And thou shalt cleanse it from sin upon the altar. That this signifies purification from evils in heaven and in the church, is evident from the signification of "cleansing," as being to purify; from the signification of "sin," as being evil, for all the evil from man is called "sin;" and from the signification of "the altar," as being a representative of the Lord as to Divine good, and of the worship of Him (see n. 9714, 9964), here as to Divine good in heaven and in the church. As the subject treated of is still the influx, presence, and reception of the Lord there, hence it is that by "the altar" is also signified heaven and the church in respect to the reception of Divine good from the Lord there; for it is the Divine of the Lord which makes heaven and the church, because the Lord dwells there in His own, and not in man's own. Hence also it is that by "the altar" is likewise signified the man himself in whom is heaven, or in whom is the church, thus in whom is the Lord; and abstractedly from person "the altar" denotes the good itself which is from the Lord with the angels of heaven and with the men of the church.
 In these senses "the altar" is mentioned in John:
There was given to me a reed like unto a rod; and the angel stood, saying, Measure the temple of God, and the altar, and them that worship therein (Rev. 11:1).
In this passage "the temple of God" and "the altar" denote heaven and the church, "the temple" denotes the spiritual church, and "the altar" the celestial church; "to measure" denotes to know the quantity and quality of truth and good, and therefore it is not only said, "Measure the temple and the altar," but also "them that worship therein." (That "the temple" denotes the spiritual church, see n. 3720; and that "to measure" denotes to know the state of a thing as to truth and good, n. 9603.) Again:
I heard another angel from the altar saying, Lord God Almighty, true and righteous are Thy judgments (Rev. 16:7);
"from the altar" denotes from the inmost heaven, where celestial good reigns; celestial good is the good of love to the Lord. In Jeremiah:
The Lord hath forsaken His altar, He hath abhorred His sanctuary (Lam. 2:7);
"to forsake the altar and the sanctuary" denotes to forsake everything of the church; "the altar" denoting everything of the church in respect to good, and "the sanctuary," everything of the church in respect to truth.