"When Paul applies the word hilasterion [expiation] to Jesus, designating him as the seal of the Ark of the Covenant and thus as the locus of the presence of the living God, the entire Old Testament theology of worship (and with it all the theologies of worship in the history of religions) is 'preserved and surpassed' and raised to a completely new level. Jesus himself is the presence of the living God. God and man, God and the world, touch one another in him. The meaning of the ritual of the Day of Atonement is accomplished in him. In his self-offering on the Cross, Jesus, as it were, brings all the sin of the world deep within the love of God and wipes it away. Accepting the Cross, entering into fellowship with Christ, means entering the realm of transformation and expiation."
--Benedict XVI, Jesus of Nazareth--Holy Week: From the Entrance into Jerusalem to the Resurrection (San Francisco: Ignatius Press, 2011), pp. 39-40