For Roman Catholics, there are some very important beliefs underlying the Mass:
The Mass is in some way a sacrifice, not just a remembrance of past events. In it Christ renews the original and voluntary sacrifice of his life to God for the sins of the world. Through the Mass he makes that sacrifice present for all worshippers.
When they are consecrated in the Mass, the bread and wine change into the actual body and blood of Christ. This belief is called 鈥榯谤补苍蝉耻产蝉迟补苍迟颈补迟颈辞苍鈥. During the Mass there is the real presence of Christ in the bread and wine through the power of the Holy SpiritThe third element of the 'Trinity' (God is the Father, the Son and the Holy Spirit). The Holy Spirit is active as God's presence and power in the world..
St Thomas AquinasA Christian monk and theologian (1225 - 1274). His ideas, such as the just war theory, have had a great influence on modern philosophy. taught that the Eucharist does for the spiritual life what food does for the body 鈥 it helps a person to grow and stay healthy. The Eucharist can give a worshipper spiritual energy and help them grow in their faith as they develop the gifts of the Holy Spirit 鈥 faith, hope and love.