Heb 3:14 For we are made partakers of Christ, if we hold the beginning of our confidence stedfast unto the end;
In the New Covenant, believers don’t need to take communion in order to “partake” of Christ, as they do that by simply believing in Christ’s atonement.
Heb 4:3 For we which have believed do enter into rest….
Heb 4:9 There remaineth therefore a rest to the people of God.
Heb 4:10 For he that is entered into his rest, he also hath ceased from his own works, as God did from his.
What this is saying, is that after Christ no one can WORK for their salvation, for the work of salvation has been COMPLETED BY JESUS. We enter into His rest through our faith in His finished work of salvation/redemption. There is absolutely NOTHING we can do to EARN our salvation – that is what’s being spoken of here in the book of Hebrews.
Rom 7:6 But now we are delivered from the law, that being dead wherein we were held; that we should serve in newness of spirit, and not in the oldness of the letter. Rom 10:4 For Christ is the end of the law for righteousness to every one that believeth. Gal 2:16 Knowing that a man is not justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be justified by the faith of Christ, and not by the works of the law: for by the works of the law shall no flesh be justified.
Gal 6:2 Bear ye one another’s burdens, and so fulfil the law of Christ – “law” (nomos) is “the moral instruction given by Christ, especially the precept concerning love.” NOTE: There are two different definitions of “law” seen in these passages, one refers to the Mosaic law (by which no one is saved), the other to the law of Christ in the New Covenant; the context of the passage determines which meaning is to be applied.
What changed in the New Covenant?
1) Heb 7:12 For the priesthood being changed, there is made of necessity a change also of the law.
The Priesthood – From the Levitical priesthood under Aaron, which offered animal sacrifices for sin, to the Everlasting Priesthood after the order of Melchisedek in which the offering of Christ’s Body & Blood put an END to the old sacrifical system because the sacrifice of Himself fulfilled the LAW of the shedding of blood to atone for sin – “once and for all.” Thus, after Christ’s death, NO MORE OFFERING is needed to atone for man’s sin, as it was FINISHED, completed when Christ breathed His last breath on the Cross. That’s why Jesus uttered this when dying, “It is finished!” He meant that the redemption of mankind was finished because His shed Blood was enough to procure full atonment for all the sins of mankind once and for all time.
Heb 7:26 For such a high priest became us, holy, guileless, undefiled, separated from sinners, and made higher than the heavens; (This is speaking of Jesus!)
Heb 7:27 who needeth not daily, like those high priests, to offer up sacrifices, first for his own sins, and then for the sins of the people: for this he did once for all, when he offered up himself.
Therefore, no communion service in the modern Church age, in which it is claimed that Christ’s body must be “offered” repeatedly and His blood shed repeatedly to atone for men’s sin can be true, since Christ already FULLY atoned for men’s sin by the “ONCE FOR ALL TIME OFFERING OF HIMSELF” when He died on the Cross.
The Catholic Communion is not merely SYMBOLIC like it is in Protestant communion services, but much more. The Catholic Church believes that the wafer of bread the priest blesses, actually becomes the Body of Christ which when eaten, atones for a person’s sin. They likewise believe that the wine they bless becomes the actual Blood of Christ. This process is called, “Transubstantiation” means that the SUBSTANCE of the wafer and wine are changed or transformed by the prayers of the priest presiding over the mass. See also http://spirit-wind.org/2019/02/
Definition of transubstantiation – the miraculous change by which according to Roman Catholic and Eastern Orthodox dogma the eucharistic elements at their consecration become the body and blood of Christ while keeping only the appearances of bread and wine. 
Roman Catholics believe that the priest consecrates the wine and the bread and it actually mutates and changes into the body and blood of Christ. This process is also known as transubstantiation. Transubstantiation was defined by the Roman Catholic Church at the Council of Trent:
“… By the consecration of the bread and wine there takes place a change of the whole substance of the bread into the substance of the body of Christ our Lord and of the whole substance of the wine into the substance of his blood. This change the holy Catholic Church has fittingly and properly called transubstantiation.” By the consecration the transubstantiation of the bread and wine into the Body and Blood of Christ is brought about. Under the consecrated species of bread and wine Christ himself, living and glorious, is present in a true, real, and substantial manner: his Body and his Blood, with his soul and his divinity (Council of Trent: DS 1640; 1651).
Christians who deny transubstantiation believe Jesus was using figurative language to teach spiritual truth. Feeding on Jesus’ body and drinking his blood are symbolic actions. They speak of someone receiving Christ wholeheartedly into their lives, not holding anything back. Protestant churches reject the doctrine of transubstantiation, believing the bread and the wine are unchanged elements used only as symbols to represent Christ’s body and blood. The Lord’s command regarding Communion in Luke 22:19 was to “do this in remembrance of me” as a memorial of his enduring sacrifice, which was once and for all. 
The Transubstantiation teaching seriously conflicts with the teachings of the Bible, a book which is the very word of God. Who then should men believe, the words of a priestcraft or the words of God Himself?
2) The Law was also changed — Heb 7:12 For the priesthood being changed, there is made of necessity a change also of the law. Heb 7:18 For there is verily a disannulling of the commandment going before for the weakness and unprofitableness thereof.
The “weakness” and “ineffectiveness” of the old covenant law was its animal sacrifices. Note: it doesn’t say “in” the law, but “of” the law. Was this a correct translation or not, and if it was, does it make a significant difference? “In” would suggest just part of the law was changed, while “of” would suggest that ALL of the law was changed.
“disannulling” = cancellation, abolition, putting away, rejection. “of the commandment going before…” (Note, the singular usage of “commandment.”)
Heb 7:19 For the law made nothing perfect, but the bringing in of a better hope did; by the which we draw nigh unto God.
The “better hope” by which “we draw near to God,” is that the way has been opened for us to enter into intimate fellowship with the Living God through the Blood of Jesus – no need for a human intermediary such as a priest, or for animal sacrifices which were only a shadow and a temporary substitute until Christ arrived and shed His Blood, thereby fulfilling the legal requirement of blood atonement.
Heb 9:28 So Christ was once offered to bear the sins of many;
Heb 10:10 By the which will we are sanctified through the offering of the body of Jesus Christ once for all.
Heb 10:11 And every priest standeth daily ministering and offering oftentimes the same sacrifices, which can never take away sins:
Heb 10:12 But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God; Heb 10:14 For by one offering he hath perfected for ever them that are sanctified. Heb 10:17 And their sins and iniquities will I remember no more.
Heb 10:18 Now where remission of these is, there is no more offering for sin.
These verses clearly state that Jesus only needed to “die once” for the sins of mankind, so He doesn’t need to be offered as a sacrifice for sin over and over again as is done in the Catholic Mass.
The Catholic religion SUBSTITUTES its communion mass for Christ’s sacrifice of Himself as the Atonement for men’s sin. This is contrary to Scripture, for Christ’s offering of Himself ONCE was sufficient, and need not be repeated. By repeatedly offering up Christ’s body and Blood, the Catholic religion DENIES that Christ’s death was ENOUGH to atone for sin! It’s the same as calling Him a LIAR. That makes the Catholic church and religion – ANTICHRIST! This is WHY the Spirit of God once told me that taking Communion at a Catholic church was an ABOMINATION to Him! It’s an abomination to Him because it’s substituting something for, or putting something in the place of, His once for all sacrifice of Himself for the forgiveness of sin. Anything we put in the place of God or that we worship instead of God, is an IDOL. Bowing down to a Eucharist (wafer) is unadulterated idol worship!
Definition of “antichrist” = an opponent of, over against, opposite to, (putting something) before, instead of, (or) in place of Christ.
Def. of “abomination” = a foul thing, a detestable thing; of idols and things pertaining to idolatry.
Heb 9:11 But Christ being come an high priest of good things to come, by a greater and more perfect tabernacle, not made with hands, that is to say, not of this building;
Heb 9:12 Neither by the blood of goats and calves, but by his own blood he entered in once into the holy place, having obtained eternal redemption for us. Heb 10:4 For it is not possible that the blood of bulls and of goats should take away sins.
Heb 10:19 Having therefore, brethren, boldness to enter into the holiest by the blood of Jesus,
Heb 10:20 By a new and living way, which he hath consecrated for us, through the veil, that is to say, his flesh;
SUMMARY: The new covenant is based upon a better hope and better promises, one of which is that because of Jesus’s sacrifice, men can enter freely and boldly into the Holy of Holies without a middle man, no longer needing a priest to act as intermediary. Jesus, our new high priest (Heb 9:15) is the ONLY intermediary needed between man and God.
Anyone who says they belong to Jesus Christ and is a Christian and yet doesn’t receive the knowledge and the “love of the truth,” is a liar and an antichrist! There can be no compromising when it comes to the truth, you’re either in Christ or you’re not, you either believe the bible is God’s word or you don’t.
2Th 2:10 And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.
2Th 2:11 And for this cause God shall send them strong delusion, that they should believe a lie:
2Th 2:12 That they all might be damned who believed not the truth, but had pleasure in unrighteousness.
As God’s Word states, those who stubbornly refuse to accept and to love the truth, are sent a “strong delusion” so that they will believe a lie. They will believe in a SUBSTITUTE or FALSE Christ, one who’s Blood and broken body wasn’t enough to pay for their sins so they have to sacrifice and “eat” Christ repeatedly (like the Old Covenant priests repeatedly sacrificed animals) to have their sins forgiven. Transubstantiation is not based upon Scripture, and is therefore a extra-biblical teaching.
The Catholic “wafer” is an IDOL because it’s a substitute for the death of Jesus, whose sacrifice once offered was enough to atone for all men’s sin for all time. The “strong delusion” is men believing that their religious works are enough to get themselves saved; works like going to confession, taking communion, giving of tithes/offerings, wearing of scapulars, lighting candles, praying to dead saints, etc. These kinds of “works” follow the pattern of men down through the Ages, men like Cain who offered the fruits of his labor to God instead of a slain animal like Abel did – Genesis 4:3. Man’s works were also represented by the fig leaves which Adam and Eve covered themselves with after they sinned against God’s command to not eat of the Tree of Knowledge of Good and Evil – Genesis 3:7. Man has since that time been trying to atone for his sins in some way other than God’s way. All man made substitutions for Christ and His death, are detestable ABOMINATIONS which no true Christian having a knowledge of God’s Word, would submit to. Ignorance is no excuse however for those who can read and have access to a bible but are just too lazy to seek the truth! Also, those who understand what they’re doing and knowingly partake of such spiritual abominations will lose their souls. Don’t be one of them! You have been forewarned by Scripture and by me.
Dear reader, what you believe and practice, is a matter of eternal life or eternal death. That’s why it’s so important that you open your heart and mind to receive these truths. Rejecting God’s words will damn your soul to everlasting torment in hellfire, so for your sake, get your heart right with God before Christ returns to earth, for then there won’t be time to do so. (Mt 25:1-13)
You have a choice – either cling to the “dead works” of religious doctrines, or receive the truth. You either trust in the finished work of Christ’s death on the Cross for your salvation or you don’t, but in order to be saved, you must believe it and receive it (apply it to yourself) – or be lost forever.