Catholicism to Christianity Part 2: Essential Doctrinal Differences


                                                            (written with the assistance of J.P. Wilhelm)

The Lord teaches us that we are to speak the truth in love. Both of those requirements – truth and love – can only be accomplished if we confine ourselves to using Scripture; otherwise we run the risk of having merely a heated debate. Scripture is truth; it is powerful. By depending upon Scripture we do not sink to merely sharing our “opinion”; rather what we state is the Word of God. Therefore, it is a firm foundation that can be stated calmly since it stands on its own.

2 Timothy 3:16 (NIV) 16All Scripture is God-breathed and is useful for teaching rebuking, correcting and training in righteousness…

John 17:17 (AMP) Sanctify them by Thy truth. Thy Word is truth.

Hebrews 4:12 (NIV)  12For the Word of God is living and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart.

The “soul” of emotionalism, family tradition and errors will be invalidated as we closely adhere to the spirit – the Word of God – which will also provide the teaching and correction to overcome the  misleadings Catholics have believed for so long. Only truth can combat error. The Word of God is our only effective tool to lead Catholics from darkness into the light and the love of Jesus.

The Roman Catholic Church (RCC) upholds four fundamentals of the Christian faith:

  • the Trinity (there are three Gods in one Divine Godhead);
  • the virgin birth (Jesus was conceived by the Holy Spirit and born of a virgin);
  • the bodily resurrection of Jesus (Jesus died and rose again) and the deity of Christ (Jesus is the Son of God).
  • The Deity of Christ (Jesus is the Son of God)

However, this is where their paths part:

  • the RCC states that Christ’s work of redemption is not finished and that His atonement is not
  • it states that the Bible is the Word of God, but holds tradition and laws passed down by the Pope above the Word of God.
  • in addition, the RCC also erroneously believes that Mary is co-Redeemer and co-Mediator with Jesus.
  • finally, Catholic teaching opposes the doctrine most essential to the Christian faith – the doctrine of justification by faith alone. The RCC not only denies this doctrine but also condemns anyone who believes it.


The purpose of this paper is to present facts. To that end, there will be basically two areas of reference: Catholic sources such as the Catholic Catechism itself plus Catholic books with the imprimatur (free from Catholic doctrinal error) of the Catholic Church on one hand and, the Bible and Bible references on the opposite side. The facts will then speak for themselves.


The crux of the Catholic’s life is the Mass. We will discuss exactly what the Mass is and its impact upon the atonement and the person and deity of Jesus through the following aspects:

What is the significant difference between the Catholic crucifix and the Protestant cross?

What is the significant difference between the Catholic wafer (and sometimes cup) and the Protestant bread and cup?


It Is Finished

Have you ever wondered why Christians have an empty cross on their altars while Catholics have a crucifix with Jesus still hanging on the cross on their altars? The answer is very simple: the RCC denies that Jesus’ work on the cross is finished. 

How the RCC interprets the “it is finished” of the cross:

“The sacrifice of Christ and the sacrifice of the Eucharist (Mass) are one single sacrifice…the same Christ who offered Himself once in a bloody manner on the altar of the cross is contained and offered in an unbloody manner in the Eucharist”[1367 from the official Catholic Catechism]

“Every time this mystery is celebrated the work of our redemption is carried on” [1405]

The sacrifice “is offered in reparation for the sins of the living and the dead” [1414]4

 Over and over again in Roman Catholicism, Jesus dies on the cross as the eternal victim.

Please note the full title of the Catholic Mass – it is the Holy Sacrifice of the Mass. According to the Catholic Church, the Mass is “a true and proper sacrifice,” [171] not merely a symbolic rite. The Catholic Catechism teaches that the reason the Mass is the same sacrifice as that of Calvary is because the victim in each case is Jesus Christ. In fact, they refer to the bread of the Eucharist as the “host” which is the Latin word hostia and  literally means “victim.In the sacrifice of the Mass, Christ is immolated [183]. Immolation is the sacrificial killing of a victim. Christ does not suffer and pour out His blood at the Mass. However, it is :

“an unbloody immolation” [184] by which He becomes sacramentally present under the appearances of bread and wine, a “most holy victim” [1085,1353,1362,136,1367,1383,1409,1545].

The sacrifice is real and the offering is real: the priest “offers the immaculate Victim to God the Father, in the Holy Spirit.” [173]

The Church teaches that the sacrifice of the cross and the sacrifice of the Mass are “one and the same sacrifice” [175].

So that each time a Mass is offered by a priest Jesus is re-presented as a sacrifice to the Father.

Roman Catholicism misrepresents the finished work of Christ on the cross by saying that the sacrifice of the cross is continued in the Mass. It has even gone so far as to state that:

these words [“ It is finished”- John 19:30] do not declare that His sacrifice was finished, but that He had finished His former, normal, earthly life and was now fixed in the state of a victim…He then began His everlasting career as the perpetual sacrifice of the new law. (The Sacrifice of Christ by Richard W. Grace) [ed. All published Catholic books carry the “imprimatur” which is the official approval of  the RCC]

The Bible says only one perfect sacrifice was needed:

  • The Bible teaches that Christ presented the sacrifice of His life to the Father only once. He “entered the holy place once for all, having obtained eternal redemption” (Hebrews 9:12).
  • The Father accepted the perfect sacrifice of Christ without reservation. “Now where there is forgiveness of these things, there is no longer any offering for sin” (Hebrews 10:18).
  • Heb 7:21b “The Lord has sworn and will not change his mind: ‘You (Jesus) are a priest forever.’ Heb 7:22 Because of this oath, Jesus has become the guarantee of a better covenant. Heb 7:23 Now there have been many of those (Old Testament) priests, since death prevented them from continuing in office; Heb 7:24 but because Jesus lives forever, he has a permanent priesthood. Heb 7:25 Therefore he is able to save completely those who come to God through him, because he always lives to intercede for them. Heb 7:26 Such a high priest meets our need—one who is holy, blameless, pure, set apart from sinners, exalted above the heavens. Heb 7:27 Unlike the other high priests, he does not need to offer sacrifices day after day, first for his own sins, and then for the sins of the people. He sacrificed for their sins once for all when he offered himself. Heb 7:28 For the law appoints as high priests men who are weak; but the oath, which came after the law, appointed the Son, who has been made perfect forever.
  • For this reason Scripture repeatedly calls the cross the once-for-all offering of Christ (Hebrews 7:27; 9: 26,28; 10:10; Romans 6:10; 1 Peter 3:18).

“When Paul wrote that ‘Christ our Passover also has been sacrificed’ (1 Cor 5:7), he put the verb in a form expressing the action as an event in past time. Christ is not being sacrificed; He has been sacrificed on the cross.  Just before the Lord gave up His spirit on the cross, He cried out, ‘It is finished!’ (John 19:30). His sacrificial work of redemption was done. To translate it in the original, it would read ‘It has been finished and stands complete.’ The whole debt is paid” (McCarthy pp.162-6)


Under the introductory section of this paper it is stated that the RCC upholds four fundamentals of the Christian Faith, one of them being the bodily resurrection of Jesus (Jesus died and rose again). Let us consider this more carefully in full light of the Scriptures and Catholic doctrine.

Where does the Bible say that Jesus is presently?

Colossians 3:1(NIV) 1Since, then, you have been raised with Christ, set your hearts on things above, where Christ is seated at the right hand of God.

Hebrews 8:1 (NIV)  1The point of what we are saying is this: We do have such a high priest, who sat down at the right hand of the throne of the Majesty in heaven (also Heb 12:2)

Scripturally, Jesus is presently “seated at the right hand of God.”

Where does the RCC say Jesus is presently?

According to Catholic doctrine Jesus is, instead, still on the cross where He is being “re-presented” at each Mass. Therefore, He has never truly died “once for all” but is perpetually dying. While Catholics may celebrate the Resurrection and the Ascension as related in Acts 1, these are rather ambiguous concepts since neither act is clear-cut in the Catholic Church.

Additionally, Jesus is still here, according to Catholic doctrine, in another form: in the Eucharistic host. Catholics are to:

“hold the Eucharist (wafer) in highest honor…worshipping it with supreme adoration…with the same worship that we offer to God” [147,148].

When the priest during the Mass holds up the “Eucharistic wafer” and says “This is the Lamb of God, happy are those who are called to His supper”, he is saying that the wafer is literally the Lamb of God, Jesus.

                                                    THE MONSTRANCE

After the wafer has been transformed into Jesus by the priest, it is placed into a special holder called the monstrance before which the people bow and worship – genuflect. There are also special feasts centered around the Exposition of the Blessed Sacrament wherein the wafer is placed in a glass receptacle, mounted in an ornate gold monstrance in the shape of a huge sunburst for the people to adore and worship as part of a special procession through the streets, especially on the feast of Corpus Christi, the Body of Christ. I participated in these processions each year when I was a child and genuflected each time I went into church. All of this was done by me – and I would assume by all who did them – with the deepest reverence and most tender of hearts. We thought we were doing all this unto the Lord. We simply knew no better. Always remember that fact when you share this new-found knowledge with Catholics as you tell them the truth about Jesus and His Word. Because, sadly, these procedures are not in accord with the second commandment in Exodus 20:4-5;

Thou shall not make unto thee any graven image… Thou shall not bow down thyself to them.

Catholic and Christian doctrines are diametrically opposed with regards to Jesus Christs’s sacrifice and its importance. Catholic doctrine teaches that Christ must die continually for his death to be of any significance. The Bible teaches the opposite – that Christ’s sacrifice was once-for-all and that He lives presently with God in Heaven. To re-emphasize, these differences must be taught in love, lest they lose their purpose.


Information for the above was obtained from Roman Catholicism: Scripture vs. Tradition by Mike Gendron, head of “Proclaiming the Gospel;” James G. McCarthy, author of The Gospel According to Rome and Conversations with Catholics; and T.A.McMahon of “The Berean Call.” All are former Catholics and present-day born-again Christians with ministries to Catholics. The classic book “The Two Babylons” by Alexander Hislop is also used as a reference.

Annotated bracketed references to Catholic doctrine were obtained from the current official Catechism of the Catholic Church and the Austin Flannery edition of Vatican Council II: The Concilar and Post Concilar Documents.

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