Exodus
+ NewThe Aseity of God — Exodus 3:14
At the burning bush God names himself in Exod 3:14: "I AM WHO I AM." The divine name discloses God's self-existence — he depends on nothing outside himself for his being. Aquinas built his metaphysics on this text, naming God ipsum esse subsistens, being itself. Augustine contrasted God's unchanging 'I AM' with the mutable creature that merely becomes. Bavinck made aseity the root of all the incommunicable attributes. Jesus invokes this very name in John 8:58, "before Abraham was, I am," claiming divine self-existence for himself. The God who simply is stands behind the sovereignty of Eph 1:11.
The Passover and the Lamb of God — Exodus 12 and John 1:29
Exod 12:21-27 institutes the Passover: a lamb without blemish, its blood on the doorposts, and the LORD passing over the houses so marked. Israel is redeemed by substitutionary blood and a shared meal. Calvin read the Passover as a sacrament of the old covenant, pointing to Christ, and Augustine saw in the lamb a figure of the crucified Lord. John the Baptist names Jesus "the Lamb of God who takes away the sin of the world." The Passover lamb of Exodus is fulfilled in the Lamb of God of John 1:29 and becomes the framework for the Lord's Supper in 1Cor 11:23-26. Paul says plainly, "Christ our Passover lamb has been sacrificed" in 1Cor 5:7.
The Lord's Supper — 1 Corinthians 11:23-26
1Cor 11:23-26 hands on the words of institution: "this is my body... this cup is the new covenant in my blood... do this in remembrance of me." The meal proclaims the Lord's death "until he comes." Aquinas articulated transubstantiation as the mode of Christ's presence, which Calvin rejected in favor of a true spiritual feeding by the Spirit. The Catechism summarizes the Catholic eucharistic faith. The Supper has been the central sacramental dividing line of the church. The "new covenant in my blood" fulfills Jer 31:31 and the Passover of Exod 12:23. The shared loaf expresses the one body of 1Cor 12:12.