When celebrating the sacraments, some Christians focus on the holiness of the elements (bread, wine, water).* And this is good. It is beneficial to stop and reflect on the ways that everyday objects can speak to us of divine realities of grace, forgiveness, promise and fellowship, even to wonder at the sacredness of all creation in pointing to God's beauty, mystery, wisdom and power. We worship a God who became flesh and blood, ate bread and wine, washed in water and shared the very air we now breathe. The incarnation is thus the main theological grounding for refusing to draw a sharp line between the physical and the spiritual. The divine Spirit sanctifies physical objects to point us towards and bring us into the presence of, and union with, Jesus.
*Leaving aside for the moment the question of how many sacraments there are and proceeding on the minimalist assumption of the two on which nearly all agree: Holy Communion and Holy Baptism.
Yet too much focus on the elements themselves can lead to some sacraments being exercises in holy carefulness, lest the body and blood of Christ be wasted or disrespected, lest any be dropped, lost or inadvertently trodden underfoot. At its extreme, only priests can handle the elements, bread-like wafers replace everyday bread, the boisterous unpredictability of children is excluded until such time as they are able to participate with due solemnity, a special plate is held under the mouths of communicants to catch any wayward pieces, and sometimes lay people are not trusted with the cup at all.
But this is not the only way of conceiving of the holiness of sacraments. Instead, or perhaps alongside, of the Spirit sanctifying everyday objects, perhaps we may also speak of the Spirit sanctifying human actions. The washing of baptism and the sharing of communion (or the thanksgiving of the eucharist, depending on linguistic preference) become enacted parables of the kingdom, pointing in the performance of them to the spiritual realities of spiritual cleansing through immersion into the life of Christ, spiritual feeding upon the saving death of Christ. If so, then it is not such much the bread and wine themselves that are special, but the eating of them in thankful fellowship, remembering Christ's death and embracing the promise of his coming.
And if we thus shift the focus from holy elements to holy activities, then we may end up with a different set of assumptions about how to proceed. If we think of holy washing (baptism) and holy sharing/thanksgiving (communion/eucharist), then the human acts are foregrounded, rather than the physical objects used in doing them. God is manifest not simply in the atoms of alcohol, simple carbohydrates, water, ethyl acetate and so on, but in the act of drinking in fellowship with others. And if we make this shift, then rather than ensuring nothing is done to conceivably dishonour the elements in any way, the focus is on honouring the actions.
When sharing a meal with friends, you're not going to deliberately dump the food on the floor, but you're also not going to obsess over avoiding any tiny spill or mess. What is important is that the food mediates joyful, honest, reciprocal relationships. A meal in which everyone is doing their utmost not to leave a skerrick or morsel wasted or out of place is probably not a meal in which everyone is enjoying one another's company.
Exegetically, this distinction turns upon the two meanings of "body" in 1 Corinthians 11.29:
For all who eat and drink without discerning the body, eat and drink judgement against themselves.Traditionally, many interpreters took "body" (soma) to mean the presence of Christ in the elements. Thus, those who fail to discern the body are unbelievers, or those who lack due reverence for the elements. The corollary is that it is better to fence off communion from the young, the ambiguously repentant, the partially orthodox, lest we encourage them to eat and drink judgement upon themselves. Better to accidentally exclude someone who could have been included than include someone would ought to have been excluded. And better to ensure that no one fails to show due respect to the body and blood of Christ, even by accident, than to open the possibility of mess.
But we must read verse 29 in the immediate context of verses 17-22, where the apostle Paul scolds the Corinthians for failing to acknowledge one another, with some (likely the wealthy) stuffing themselves at the holy meal before others (likely the slaves) had a chance to turn up. His criticism is not that they were disrespecting the body of Christ through disrespecting the elements, but disrespecting the body of Christ through disrespecting their fellow believers. They show "contempt for the church God" through "humiliat[ing] those who have nothing" and through the divisions and factions they have allowed to form within the body of believers. The entire letter emphasises this problem, from the opening salvo in 1.10-17 through to the famous "body of Christ" passage in 12.12-31, which in turn leads into the even more famous love-poem in 1 Corinthians 13 (which is more about how Christians are to treat one another as a church than about a healthy marriage, despite its near ubiquity in weddings). Therefore, in both the immediate context and the context of the whole epistle, it is far more natural to read "body" in 11.29 as the body of believers. Thus, those who eat and drink judgement upon themselves are those whose celebration of the holy meal is insufficiently interpersonal, insufficiently attentive to our neighbour, insufficiently focused on the act of eating in fellowship and thankfulness. On this reading, it is better to include some who perhaps ought to have been excluded than to exclude anyone who really ought to have been included. Ironically, the reading of "body" that emphasises the holiness of the elements can itself sometimes be the cause of our failure to honour one another or the holiness of the sharing Paul (and Jesus) invites us into.
Bottom line: when it comes to celebrating sacraments, the more the merrier. Share with children. Share with the ambiguously faithful, the confused and doubting, the seeking and struggling. Share with the sick and with those whose hands shake so much that they might spill. Obsess less over what ends up on the floor and more on the faces with whom we share a gracious feast of love.
Baptisms should leave the floor wet. Communion should leave holy crumbs.