Article 29

The wicked who partake of the Lord’s Supper do not eat the body of Christ.

The wicked and those who lack a living faith, although they physically and visible “press with their teeth” (as St. Augustine says) the sacrament of the body and blood of Christ, nevertheless are in no way partakers of Christ.  Rather, by eating and drinking the sign or sacrament or so great a thing, they bring condemnation upon themselves.