Holy Communion is a sanitised form of religious violence. All religions of the past held that their divinities got magical power to help them from sacrifices. So priests murdered animals and children on altars for the blood to come out and give magical power to the gods or God. The Bible God says that life is in the blood and the blood is in the life. Eating blood was banned for that reason. Clearly God thought that if you took animal blood you became some kind of lesser human, you became a kind of animal. That is one case of how the Bible opposes evolution. Evolution says we came from animals and in fact still are animals.
To forge an alliance with the deity, the sacrifice was consumed as a sign of union with it and it with you.
The Old Testament rites were excessive in bloodletting and evil. Animals were offered and blood splattered all over the sanctuary.
The Church imagines that this depicted the death of Jesus and doesn't have to be done any more. So it is not against this savagery in principle.
Jesus supposedly gave us a new sacrifice, an unbloody one. Before his death, he took bread saying, "This is my body which is given for you." And, "This is my blood which is shed for your sins so that they might be forgiven. Do this and remember me."
This is about forming the communicant into somebody like Jesus who is willing to have their body broken for the greater good and their blood drained out in violence. It is linked to his doctrine that whoever follows him must take up the cross and be ready to lose his life for it profits nobody anything to gain all in this world and lose his soul.
Real union with the sacrificing Jesus and others would mean you implicitly and by proxy embrace crucifixion.
No sane person wants their child to think like that. The rite of first communion which happens when a child is about 8 years old is pure hypocrisy for no child does think like that. The viciousness and fanaticism is downplayed by teachers and priests and parents so that this social tradition and cultural symbol can proceed in the guise of authentic Christian faith.
Catholics put children forward for first communion regardless of them being disturbed by this body and blood consuming ritual. Children that would refuse are bribed with the thought of having a special day maybe a white dress and a dinner and getting gifts of money. Actions speak louder than words so the spiritual superficiality of the participants and parents says something. They sense something is wrong deep down. So they use deflection.
The notion that the communion wafer is a living man and indeed a man who is saved and is more alive than us leads easily to the assumption that abortion is wrong for a ball of cells might be a real person with full rights. Jesus’ soul is the soul of the wafer so it follows your keyring could be a person. Yet Catholicism denies you the right to suggest that your keyring is your father. Anyway, it is easy then to see a zygote as a person with as much of a right to live as a forty year old. The fanaticism of this rite is obvious.
For any person to cooperate in first communion is shameful. It is even more shameful if it is just about parties and cultural religion. Yet the parents would be the first to complain if parties were held for children to celebrate the suicide of Hitler even if those were passed off as mere traditions and cultural emblems and did not imply any real gloating.