I think perhaps my question was misunderstood. Perhaps, I did not ask it as specifically as I thought. Nonetheless, thank you for the replies. I was not referring to the Eucharist itself, but the teaching that in the (wine) blood, therein contains the Body, Soul, and Divinity. and in the (Host) Body, therein contains the Blood, Soul and Divinity. When Jesus clearly made a distinction between his Body and his Blood.
Thanks
Most of that comes from Logic.
Christ Himself was present took on human form. He was living, he had a body, he had blood.
Therefore, according to Platonic philosophy ( which was the predomination philosophy of the time, and the metaphysical aspects of that have been adopted by the Church. Aquinas based most of his work on Plato.
The union of body and blood in a living person was a Substance in Platonic metaphysical philosophy. It was an individual person, therefore a unique mode of existance.
Christ living is one substance.
In addition, the animating principle of the body is the soul. The presence of a soul is what distinguishes living matter for dead matter.
Thus is follows in the philosophy of the day, and of the current philosophy of the Church, that the Eucharist, if it truely is the Substance of Christ, the Second Person of God, must contain
Body and Blood must be present together, as Christ is living. His Soul must be present, as gain, he is living, the soul of Christ is the animating principal of His Body.
His Divinity is present, as He is God.
Since Christ is living, His Body and Blood are not, nor can they be, seperate. They are united in the Substance of Christ.
All of this was well known in the time of Christ, as it is common Platonic metaphysics. St. Paul and St. Luke, as educated men, would have understood this and included this explaination when discussing theology with other educated men, especially Greeks.
Christ instituded the Eucharist as seperate species, not seperate substances, to indicate that he would die. And that is how we know that the Sacrifice of the Mass is a representation of the Sacrifice of Cavalry. It why the species are consecrated seperately, to show His Death. But in their reception we receive the single substance of Christ Himself, alive and resurrected, Body and Blood together, Living, so the Soul is present, and the Second Person of the Holy Trinity, so His Divintiy is there.
All this would have been know to any educated person at the time of Christ who believed that the Eucharist is the reception of the Living Christ.