If so, then Jesus Christ and the Holy Spirit are in essence hijacked out of "the Church".. They are made to be ancillary to clergy and ceremony.. BUT imported by transubstantiation which is magic and superstition.. in the mysterious way all mystery religions operate..
The Holy Spirit is a real and vital entity.. More real than the Sun and the Moon since he made the Sun and the Moon.. The Holy Spirit does not need clergy or ceremony to operate.. or dogma.. clergy does.. and pagans do.. After all is God, God?.. You know, the real one.. there are many Gods but only one real one.. The pretenders(pagans) Need ceremony and clergy.. and outward displays.. The paraclete(Holy Spirit) can come by your(or my) side wherever we are to "help", comfort and instruct..
NOTE: Transubstantiation = making a metaphor literal(eat my flesh and drink my blood).. its like saying "its raining cats and dogs and then running to the window to see pets falling as precipitation..
Of a truth, the Catholic Church is not alone in having doctrine and tradition which exclude other beliefs.
But God knows His own family.
And since only His opinion matters, I find such exclusions to be moot.
Christ pointed to a piece of bread and said “eat it, this is my body” (in all synoptic gospels). When challenged on whether he meant it in the literal sense, He made it clear that indeed, “unless you gnaw on it, you will not have eternal life” in the Gospel of St. John. [...] After His resurrection, moreover, He performed another miracle: He appeared to the disciples in Emmaus in such a way that they only recognized Him in the bread. St. Paul also taught the Corinthians that they should “discern” the body of Christ in the Communion. This describes what is known as Real Presence of Christ in the Eucharist. All we do at this point is take the scripture, the words of Christ, literally. I am aware of other interpretations, — that He meant it in some nonliteral sense, but they do not convince me.
The Real Presence is the fundamental Catholic doctrine. It is also the Orthodox belief, and Martin Luther’s belief, and I can point you to Christian writings from the 1st Century that describe the same doctrine, so it is also the historical doctrine since the beginning of Christianity.
The question arises, — How can bread (or wine), which our senses continue to perceive as bread, become body, blood, soul and divinity of Christ? What is the mechanism of the Real Presence?
The answer to this could not be given till the synthesis of classic aristotelian philosophy and Christianity occurred in the Middle Ages. Prior to that, the answer was — We don’t know, just like we don’t know how Jesus walked on water or fed the thousands with five loaves and two fish. It is a miracle and a mystery. This non-explanation remains the Orthodox teaching to this day, and we, Catholics, are fine with it. It is sufficient to maintain your catholicity if you simply say “I don’t know how the Real Presence happens”. Nevertheless, the inquiring mind of St. Thomas Aquinas gave the answer, and his answer is Transubstantiation. What it means, he taught, is that everything has “substance” and “appearance” (the techical term is “accidents”). Usually when the substance changes, the appearance changes also. For example, when a log becomes fire ir looks different than a cold log. But still the substance of the log is not what enters our eyes and nostrils, the accidents of the log do. So, in principle, it is possible there to be a discrepancy between substance and appearance. Such is the case with the Eucharistic elements: the substance of the bread changes over to Christ, — the bread trans-substantiates, — but the accidents remain as before, the appearance and taste of bread.
It is similar to how the disciples are with real Jesus in Emmaus, but they see a stranger and not Jesus, till the end of their conversation.
Luther offered another explanation for the Real Presence, Consubstantiation, of which you need to ask a Lutheran.
You also asked what is the need for it. The simple answer is, it is a commandment of Christ to do it, so priests continue to do it in His name. Christ also explained what benefit it is to us, when He sad that unless we eat the Eucharist, we will not have eternal life.
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