In the Lord’s Prayer, God calls the Bread of the Presence that we Anointed Priests of his House consume in the Divine Liturgy of the Temple our “supersubstantial bread.” The doctrine implicit in this term subsumes, reconciles, and integrates all the various doctrines of the Real Presence in the Eucharist – memorial, pneumatic, sacramental, consubstantial, transubstantial, and so forth.
Of these doctrines, transubstantiation is the most inclusive – if it’s true, so are all the others – but also the most difficult to take on board:
What makes us uneasy [about transubstantiation] is that the substances of the bread and the wine seem to have been destroyed [by Grace, rather than perfected thereby]. And yet Aquinas is very concerned to show that this is not the case; the substances are not destroyed but converted.
– page 231
They are turned from their own lives, toward and into the life of God. The elements are no longer occasions of their own careers, but of God. So likewise with the communicant: “I live; yet not I, but Christ liveth in me” (Galatians 2:20).
The Host has all the properties of bread, and all the causal effects of bread. These do not disappear at the Consecration. As Caldecott says, we don’t expect the consecrated bread to look any different under an electron microscope (nor do communicants look any different after they have partaken thereof). After the Consecration, the bread still behaves like bread, whatever else it may be doing. In so far forth, then, it is indeed – literally – bread. But it is not, ultimately, merely bread. Which is to say that it *just isn’t* bread anymore. It is God. It is supersubstantial bread.
How does supersubstantiation work?
The substance of a whole is prior to the substance of any of its parts. Those parts can be understood as parts only in relation to a whole, and even then only via an act of intellectual abstraction, by which they are mentally teased out of a concrete integrity. In actuality, parts are not entities concretely disparate from the whole of which they are parts. Separate them concretely from that whole, and they will no longer be parts of it, at all.
So, when I digest molecules of bread, those molecules are no longer molecules, simpliciter. Rather, they parts of me. And entities are indisintegrable wholes: wherever I am even a little bit, there I wholly am. When I eat them, the molecules of the bread become molecules of me, and the atoms of those molecules become atoms of me. Their substances are no longer those of free-floating atoms or molecules (there are really no such things as free-floating particles, thanks to Mach’s Principle), but of me. Their individual substances are subsumed in mine.
The whole is logically prior to the part. But this means that the whole is prior to the part, period full stop.
When a thing participates in a larger whole, it does not cease altogether to be the thing that it is, or to have the character that makes it definitely the individual, specific, generic thing that it is. If that were to happen, it could not function in and for the whole, in just the way that was needful thereto, in order for the whole to cohere and coordinate properly as just itself.
But qua part, a thing is no island. As a part, it is no longer at all in order for itself; rather, it is in order for the whole of which it is a part. The participant atom does indeed exist, but – until it is concretely separated from its whole – only as an aspect of that whole. The atom has a life of its own, but so long as it is part of a molecule, the life that is its own is its perspective on the life of the molecule. It is, i.e., an aspect on, and of, the molecular life. The life of the molecular atom is provided to it as and by the life of the molecule; for the atom, that molecular life is its own atomic life. The life of such an atom is different from those of other participant atoms. But nonetheless that atomic life is an aspect of the life of the molecule.
The properties, character, operation, and form of the part contribute to those of the whole, which could not have the properties, character, operation or form that it has without them. The parts contribute to the whole: they give their being to that of the whole. Thus if you derange the nervous system, you injure its contribution to the operation of the person. But the parts receive their being qua parts from the whole. As parts, their lives are the life of the whole, given them thereby, and by them received, taken, grasped, positively prehended – and then, given back in offering and sacrifice. But this exchange and coinherence is mediated by the currency of the life of the whole.
Such is Communion: a common unity. The motions of the parts are coordinated, not as by an engineer pulling levers, but as the electromagnetic fields of the iron filings are coordinated by that of the magnet, and contribute thereto.
… since what is received in Communion is the whole Christ – the “I” of the second divine Person, in other words the actual “substance” that is Christ – what takes place in Communion is a welcoming, a reception into myself, of that entire Person.”
– page 233
NB that the second Person is consubstantial with the first and third Persons. When we partake of Jesus, then, we partake ipso facto also of his Father and of the Holy Ghost.
And when we eat God, he becomes consubstantial with us, and we therefore likewise with him. As the bread is supersubstantiated, so are we when we eat it. That is how we become parts of his Body: even after we eat the bread, it continues supersubstantiated in and as Jesus. The molecules of God become molecules of us, but do not stop being molecules of God. When we integrate them into our substance, they integrate us into his.
It might seem odd that when we eat a bit of a thing, the whole of it should supersede our own, so that our wholeness is a participant therein, rather than a thing only unto itself (“a thing only unto itself” being, again, something we never encounter in reality). But it’s no more mysterious than the covalent interaction of a hydrogen atom with a carbon atom that is part of a protein molecule. Seeking to complete the fulfillment of its electronic shell and attain rest, the hydrogen atom “devours” an electron from the outer shell of the carbon atom, and the two atoms then share the electron. But the effect is that the hydrogen atom is thereby integrated into the molecule.
But this integration operates in both directions: it is, precisely, covalent. The life of the hydrogen atom is taken into the life of the protein molecule by the covalence, and vice versa. As the Body of Jesus is like ours a procedure of the whole cosmos, and integral thereto, so likewise is the whole cosmos a procedure of the Body of Jesus, and integral thereto.
So, when we eat the Bread of the Presence, we are taken up in its supersubstantiation by its integration with our flesh.
The Holy Spirit binds … spouses together in one flesh, and a new life is created in which both are reflected. If the Eucharist did not contain the whole substance of Christ – that is, his body, soul, and person – there would be no “marriage” between myself and God, between human and divine nature, no Bride of Christ, no Church. It is therefore the very reality of the Church, and of our salvation, that is at stake in the doctrine of transubstantiation.
– page 233
The Eucharist makes the Church. It is the first stage in the realization of the fulfillment at the eschaton of the perfected Communion of the ecclesia, of the synagogue. For, by it the body of man, which is the cosmos, is joined to the substance of God, & supersubstantiated in a new life, like that of a baby born of the wedlock of male and female. The destiny of the Eucharistic elements is also our destiny. The perfection and consummation by Grace of creaturely nature – of bread, of men, of the Church, of the cosmos – is effected by its supersubstantiation.
The completion of the supersubstantiation of the human person is theosis. Theosis is the perfection of spatiosissimus: of ontological actuality, causal efficacy, phenomenal intensity and sacramental significance. God became man to make men gods; supersubstantiation is how he does it.