Aspects of a sacrament that are not required for validity can still be important.
Suppose a priest in a High Anglican or Roman Catholic* Church turned up one hot Sunday morning in the summer in a swimming costume and started to celebrate High Mass.
To the protests of the laity, and probably diocese, suppose this priest was to respond “it doesn’t matter, the Sacrament is still valid.”
I doubt most people would feel this was a good and sufficient argument…
Yet exactly that argument is used to justify the denial of Communion in both kinds, either on an everyday basis, or in regarding it as something without significant value, which it is not worth bothering with when inconvenient. I am entirely with those that feel vestments and ceremony are part of the proper celebration of the Eucharist under normal conditions. I don’t think priests should celebrate the Eucharist wearing swimming costumes, or indeed, wearing ordinary clothes, without some very good reason for it.
However, vestments are part of the tradition the church has developed for the appropriate presentation and dignity of the Eucharist, while the reception of the bread and the cup are part of the original institution: it is reasonable to argue that traditions such as vestments should be considered much less important**, than reception in both kinds. And this does not currently seem to be the case.
This may be one of the issues in which someone who has studied Christian philosophy naturally has a rather different perspective from those who come to it from theology. Validity is important, but it is properly a baseline and not a ceiling from the logical point of view. Validity is a minimum. It isn’t a be-all and end-all of what we are doing – and, as I’m pointing out with the “priest-in-swimming-costume” example, we don’t use the same argument of “not necessary for validity” as a reason not to do any other element of what we normally do. For only the priest to receive the cup – or to celebrate not dressed – in a labour camp in Siberia is all very well. But what is permissible in truly exceptional circumstances doesn’t usually serve as a good guide for everyday practice. The Sacraments are not mechanical rites, to be reduced to their minimum essential elements for fairly minor reasons, but rather things to be celebrated and received with as much fullness as possible, as part of what God has given us.
I would emphasise that I do not judge anyone’s individual spirituality, or relationship with God in the Sacrament, or personal medical needs. To receive in one kind through individual choice is different from the corporate decision to offer Communion only in one kind.
However, I would suggest that those of us to whom reception in both kinds matters devotionally and spiritually, should celebrate valuing the reception of the Chalice, rather than being ashamed of caring about it. The Cup is Christ’s gift to us too, and it is good to value his gifts, according to his way of choosing to work with us.
It does at least not logically follow that because something is not necessary for the validity of a Sacrament it is not significant and important.
*I am not a Roman Catholic, but I think there is enough shared ground here to have a sensible academic argument on the issue!
** I.e. laid aside with a far lower threshold of reasons to do differently. (For those familiar with the language: what I am saying is that I think it would make more sense to be prepared to lay aside vestments for just cause, but to require a serious reason not to offer Communion in both kinds, than the other way around).
N.B. Lest there be any confusion, I am among the Anglicans who fully endorse the Real Presence, but reject literal Transubstantiation (or any other attempt to reduce the Real Presence to a precise human theory) as trying to reduce the mystery to a bit of human thinking, though I happily regard most of the theories as useful but limited imagery to help us enter into the mystery.