"Atonement has incomparably the deepest place of all truths in scripture, save only Christ's person." (W. K., Lectures on the Pentateuch, p. 275.)
In this truly wonderful and comprehensive chapter 16 of Leviticus we get the most profound truth of propitiation Godward, typifying that great work of Christ on the cross. Only on this notable tenth day of the seventh month could Aaron enter into God's presence within the vail. For this God specified that he come "with a young bullock for a sin offering and a ram for a burnt offering." Also he was to bathe, be attired entirely with holy linen garments, have a censer full of burning coals of fire from off the brazen altar, have sweet incense to "put on the fire before the Lord, that the cloud of incense may cover the mercy seat", where he was to sprinkle the blood of the bullock to make "atonement for himself and for his house" to propitiate God for sin.
Incidentally here, although typically important, Aaron's house represents the Christian family of priests, 1 Peter 2:5-95Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ. 6Wherefore also it is contained in the scripture, Behold, I lay in Sion a chief corner stone, elect, precious: and he that believeth on him shall not be confounded. 7Unto you therefore which believe he is precious: but unto them which be disobedient, the stone which the builders disallowed, the same is made the head of the corner, 8And a stone of stumbling, and a rock of offence, even to them which stumble at the word, being disobedient: whereunto also they were appointed. 9But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should show forth the praises of him who hath called you out of darkness into his marvellous light: (1 Peter 2:5‑9); Rev. 1:66And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen. (Revelation 1:6). Aaron's acceptance in God's presence, by virtue of the blood, tells us of our being "accepted in the Beloved" (Eph. 1:66To the praise of the glory of his grace, wherein he hath made us accepted in the beloved. (Ephesians 1:6)) and our present priestly privileges of entering by faith as worshipers into the holiest (Heb. 10:1919Having therefore, brethren, boldness to enter into the holiest by the blood of Jesus, (Hebrews 10:19)).
During this present age, Israel's Messiah and Great High Priest is hidden, as it were, within the vail of the sanctuary until He comes forth for their blessings.