It may look quaint to contemporary Christians, but once upon a time there were vigorous debates about the proper posture for receiving communion.

Puritans and Presbyterians objected to the custom of kneeling to receive the elements, arguing that it perpetuated the Catholic practice of venerating the consecrated Host. In a homily delivered to Edward VI, John Hooper declared, “The outward behavior and gesture of the receiver should want all kind of suspicion, shew, or inclination of idolatry. Wherefore seeing kneeling is a shew and external sign of honoring and worshipping, and heretofore hath grievous and damnable idolatry been committed by the honouring of the Sacrament, I would wish it were commanded by the magistrates that the communicators and receivers should do it standing or sitting” (Hughes, Reformation in England, 197).

John Knox described kneeling for communion as “idolatry,” and argued that it was a posture for beggars and not for Christians, who are “the children of God, priests and kings united by Christ's blood.” He later backpedaled, saying that kneeling was acceptable and should be tolerated to avoid a “breach of charity.” (Kyle and Johnson, John Knox, 62-3).

The Book of Common Prayer showed the scars of this battle. It required kneeling, but carefully explained that it didn't imply veneration or transubstantiation.

The debate shouldn't look quaint. Matter matters, and what we do with our bodies is as important to piety as what we do with our minds (which can't operate without bodies anyway). In fact, what we do with our bodies can forge the paths our minds travel. If we adopt a posture of contrition at the table, we will develop a penitential Eucharistic piety. Sitting for communion cultivates a different form of piety.

James Jordan has pointed out that Jesus regularly commands people to “sit down” as He gets ready to feed them (Matthew 14:19; 15:35). Sitting is a posture of rest, a Sabbatical posture, and by the same token is a posture of rule: Sitting for communion, we share in Jesus' Sabbath enthronement (cf. Matthew 22:44; 20:23). Sitting (or, in the ancient world, reclining) is a posture for meals, and the Supper is, at the least, a meal. Kneeling (or standing) to receive the elements subtly convinces us that the Eucharist is something other than it appears to be, something other than a meal. Since it reinforces the meal-character of the Supper, sitting reinforces the keynote of all biblical feasts—joy. Sitting for communion helps ensure that the table remains a table instead of turning into a tomb.

I would split the difference between the two Knoxes. The moderate Knox was right: Kneeling isn't idolatry. The hard-nosed Knox was right too: Posture is important. Kneeling or standing can distort Eucharistic theology and practice. And, on the other hand, sitting for communion embodies the significance of the Supper.

It's best to do what Jesus said: Sit down.