What are creeds?
Creeds are brief formulas of faith that make it possible for all believers to make a common profession.
Brief formulas of this kind can be found already in the letters of St. Paul. The early Christian Apostles’ Creed has a special dignity, because it is thought to be a summary of the faith of the apostles. The Nicene Creed is highly esteemed because it resulted from the great councils of the Church when Christendom was still undivided (Nicaea, 325; Constantinople, 381) and is to this day the common basis for the Christian in the East and the West.
CCC section (185-188)