WCF 29.6.
That doctrine which maintains a change of the substance of bread and wine, into the substance of Christ’s body and blood (commonly called transubstantiation) by consecration of a priest, or by any other way, is repugnant, not to Scripture alone, but even to common sense, and reason; overthroweth the nature of the sacrament, and hath been, and is, the cause of manifold superstitions; yea, of gross idolatries. (Acts 3:21, 1 Cor. 11:24–26, Luke 24:6, 39)