Since it is the Feast of Saint Nicholas it seems only right to remember him for something he did during the First Council of Nicaea. This is the Council where the Nicene Creed was adopted. Now at this Council there is a rather famous moment where punches were thrown. Nicholas of Myrna couldn’t take any more of what Arius was saying about the natures and relationship of Jesus to the Father. Arius and his supporters argued that Jesus was the first and perfect creation but not God. However after hearing this for several hours according to legend Nicholas of Myrna got up and slapped Arius in the face. After doing this Nicholas was stripped of the office and thrown in jail. While in jail Nicholas prayed for forgiveness and at some point during the night Jesus and Mary appeared to him (according to different accounts Mary and Jesus appeared to the other bishops or the Emperor Constantine) Jesus and Mary gave Nicholas a book of the Gospels and an Omophorion (a sign of the office of Bishop). In the morning Nicholas was released from jail and his office of Bishop restored to him. The council agreed with Nicholas and rejected the idea of Arius, this was written in to the Nicene Creed.
This Creed is sort of the one that we can say during Sunday Mass, however the original from 325 was a bit different from what we say. The version from 325 is as follows:
We believe in one God, the Father almighty, maker of all things visible and invisible; And in one Lord, Jesus Christ, the Son of God, begotten from the Father, only-begotten, that is, from the substance of the Father, God from God, light from light, true God from true God, begotten not made, of one substance with the Father, through Whom all things came into being, things in heaven and things on earth, Who because of us men and because of our salvation came down, and became incarnate and became man, and suffered, and rose again on the third day, and ascended to the heavens, and will come to judge the living and dead. And in the Holy Spirit. But as for those who say, There was when He was not, and, Before being born He was not,and that He came into existence out of nothing, or who assert that the Son of God is of a different hypostasis or substance, or created, or is subject to alteration or change – these the Catholic and apostolic Church anathematizes.
This Creed was revised at the First Council of Constantinople in 381 and is similar to what we say at Mass.
We believe in one God, the Father, the Almighty, maker of heaven and earth, of all that is, seen and unseen. We believe in one Lord, Jesus Christ, the only Son of God, eternally begotten from the Father, God from God, Light from Light, true God from true God, begotten, not made, of the same substance as the Father. Through him all things were made. For us men and for our salvation he came down from heaven: by the power of the Holy Spirit he was born of the Virgin Mary, and became man.For our sake he was crucified under Pontius Pilate; he suffered, died, and was buried. On the third day he rose again in accordance with the Scriptures; he ascended into heaven and is seated at the right hand of the Father. He will come again in glory to judge the living and the dead, and his kingdom will have no end. We believe in the Holy Spirit, the Lord, the giver of life, who proceeds from the Father (and the Son). With the Father and the Son he is worshipped and glorified. He has spoken through the Prophets. We believe in one holy catholic and apostolic Church. We acknowledge one baptism for the forgiveness of sins. We look for the resurrection of the dead, and the life of the world to come..
Please note that italicized “and the Son” in the part after the Holy Spirit this is the filioque debate. In the Eastern Church this is not a part of the Creed however in the West it is said. In 1995, the Vatican said that the “And the Son” doesn’t work in the Greek text and therefore when the creed is said in Greek it is not included. Yet in Latin it works and so that is why the Roman Church says this and the Greek Church doesn’t. This is one of the reasons behind the Great Schism. However when the Pope is with one of the Ecumenical Patriarchs they say the Creed in Greek, perhaps a small step toward a reunion.