The Holy Eucharist, also known as, Holy Communion, Host. Many still do not believe in Transubstantiation, which is the changing of the unconsecrated host and wine into the true body and blood of our Lord Jesus Christ. This occurs during Mass, when the priest consecrates the bread and wine saying the words "This is my body...This is my blood". The priest at mass is acting in persona Christi . The Eucharist have always been the center of the Christian life, Catholics to be specific. It is because of the Love of Jesus that allows us to consume it. It also serves the purpose of maintaining the 'one holy catholic and apostolic church' as recited in the Niceno-Constantinopolitan Creed, and maintaining the Apostolicity of the Eucharist.

This aspect of the universal charity of the Eucharistic Sacrifice is based on the words of the Saviour himself. In instituting it, he did not merely say: “This is my body”, “this is my blood”, but went on to add: “which is given for you”, “which is poured out for you” (Luke 22:19-20). Jesus did not simply state that what he was giving them to eat and drink was his body and his blood; he also expressed its sacrificial meaning and made sacramentally present his sacrifice which would soon be offered on the Cross for the salvation of all. “The Mass is at the same time, and inseparably, the sacrificial memorial in which the sacrifice of the Cross is perpetuated and the sacred banquet of communion with the Lord's body and blood”.

**Read more of this in the Encyclical of Pope John Paul II 'ECCLESIA DE EUCHARISTIA'