The Lord’s Supper vs. the RC Mass

This isn’t an argument or bashing. The difference between the Roman Catholic and Protestant view of Christ’s command (Luke 22:19) instituted by our Lord may seem trivial to some, but at one time in our history resulted in violence and a 30 year war.
Roman Catholics believe the elements of bread and wine literally become the body, blood, soul and divinity of Jesus Christ and that it is a propitiatory sacrifice offered for both the living and the dead. Those in purgatory benefit from this as well.
The protestant view is that the elements are not literally Jesus but are symbolic; a remembrance of what Christ did for us, not a means of maintaining salvation.
The Council of Trent (1545) declared if anyone denies the elements are not literally (physically) Jesus Christ himself you were anathema. Being anathematized in those days was a death sentence.

The protestants took a strong stance calling the RC Mass an accursed idolatry.

Council of Trent (Roman Catholics)

CANON I. 

If any one saith, that in the Mass a true and real Sacrifice is not offered to God; or, that to be offered is nothing else but that Christ is given us to eat; let him be anathema.

CANON III.

If any one saith, that the Sacrifice of the Mass is only a sacrifice of praise and of thanksgiving; or, that it is a bare commemoration of the Sacrifice consummated on the Cross, but not a propitiatory sacrifice; or, that it profits him only who receives; and that it ought not to be offered for the living and the dead for sins, pains, satisfactions, and other necessities; let him be anathema.

Heidelberg Catechism 1563 (Protestants)

Q. 80. What difference is there between the Lord’s supper and the popish mass?
A. 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;a and, that we by the Holy Ghost are ingrafted into Christ,b who, according to his human nature is now not on earth, but in heaven, at the right hand of God his Father,c and will there be worshipped by us.d 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.e

(a) Heb 7:27; Heb 9:12,25-28; Heb 10:10,12-14; John 19:30; Matt 26:28; Luke 22:19,20
(b) 1 Cor 6:17; 1 Cor 10:16
(c) Heb 1:3; Heb 8:1,2; John 20:17
(d) Matt 6:20,21; John 4:21-24; Luke 24:52; Acts 7:55,56; Col 3:1; Phil 3:20,21; 1 Thess 1:10; Heb 9:6-10
(e) Heb 9:26; Heb 10:12,14,19-31

Luke 22:19 New King James Version (NKJV)
19 And He took bread, gave thanks and broke it, and gave it to them, saying, “This is My body which is given for you; do this in remembrance of Me.”