The essay "Holy Trinity and Catholic Faith" talks about the Holy Trinity, the central pillar of the Catholic faith. For any faith or religion, its concept of God is foundational to the life and conduct of adherents to that religion or faith. Thus the defining feature of Christianity is of a necessity, its concept of God. The doctrine of the Trinity is so fundamental to the extent that a rejection of the Trinity is tantamount to a rejection of the Christian faith as evidenced in the provisions of the Athanasian creed. Though the word ‘Trinity’ does not appear in the Bible, the doctrine of the Trinity is based on biblical provisions both in the New Testament and the Old Testament. Perhaps, the clearest reference to the doctrine of the Trinity in scripture can be found in Matthew 28:19 “Go therefore and make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit”. The Old Testament gives a glimpse of the doctrine of the Trinity in Genesis 1:26 – “Then God said, “Let Us make man in Our image”…” and in Genesis 11:6-7 “And the Lord said, … “Come, let Us go down and there confuse their language …” The singularity of the Godhead is made evident in the use of the singular ‘Then God said’ and ‘And the Lord said’. The Trinity of Persons is also made evident in the use of the plural ‘let Us’. The centrality of the doctrine of the Trinity in the Catholic Church is also made evident in the fact that it permeates the observance of the Eucharist. It can thus be said that without recognition of Jesus Christ the Son in the Godhead, the Church cannot be seen to be worshipping Him during the sacrament of the Eucharist. If He is not God, then He cannot be worshipped. The Sacrosanctum Concilium for instance states that:
"56. The two parts which, in a certain sense, go to make up the Mass, namely, the liturgy of the word and the eucharistic liturgy, are so closely connected with each other that they form but one single act of worship. Accordingly this sacred Synod strongly urges pastors of souls that, when instructing the faithful, they insistently teach them to take their part in the entire Mass, especially on Sundays and feasts of obligation."
Consequently the observance of the Eucharist, which is a memorial of the sacrifice of Jesus Christ on the cross is not just a memorial but an act of worship.