Question 80 from The Heidelberg Catechism: “What difference is there between the Lord’s supper and the popish mass? Answer: The Lord’s supper testifies to us, that we have a full pardon of all sin by the only sacrifice of Jesus Christ, which he himself has once accomplished on the cross; and, that we by the Holy Ghost are ingrafted into Christ, who, according to his human nature is now not on earth, but in heaven, at the right hand of God his Father, and will there be worshipped by us. But the mass teaches, that the living and dead have not the pardon of sins through the sufferings of Christ, unless Christ is also daily offered for them by the priests; and further, that Christ is bodily under the form of bread and wine, and therefore is to be worshipped in them; so that the mass, at bottom, is nothing else than a denial of the one sacrifice and sufferings of Jesus Christ, and an accursed idolatry.”
Travel here to read an article about the University Chorale from my alma mater, who sang last year at a Wednesday evening Mass at Saint Peter’s Basilica in Vatican City. Unsettling, that.