In context , by not effectually recognizing other members as part of the Body of Christ. But as correct intent is necessary on the part of the priest, and may be only assumed, this may give ocassion to doubt as to whether one had received the sacrament.
In context......
even in context that particular understanding of that verse is not as some here would have it. St. Paul is quite clearly speaking of the Eucharist. How else would one partake of the one loaf and drink of the one cup which unites the one body of Christ?
As a Catholic, who beliefs most fervently in the presence of Christ in the Eucharist, the non Catholic and mistaken understanding of that verse, does not counter my argument.