What is the name of the profession of faith established by the council fathers at the conclusion of the First Ecumenical Council?

The profession of faith established by the council fathers at the conclusion of the First Ecumenical Council, which convened in 325 AD in Nicaea, is known as the Nicene Creed. This Creed was formulated to address the Arian controversy regarding the nature of Christ and his relationship to God the Father.

The Nicene Creed asserts the belief in Jesus Christ as true God from true God, emphasizing the co-eternity and consubstantiality of the Son with the Father. Its establishment was a pivotal moment in Christian history, as it served to unify Christian belief against heretical views that questioned Christ's divine nature.

The other options, while significant in their own rights, reference different creeds or definitions established at later councils. For instance, the Apostles' Creed is an earlier statement of Christian belief, the Constantinopolitan Creed was an expanded version of the Nicene Creed adopted in 381 AD, and the Chalcedonian Definition, established in 451 AD, articulated Christology but is not a profession of faith from the First Ecumenical Council. The Nicene Creed remains foundational to many Christian denominations today, representing a core aspect of the faith established in response to early doctrinal disputes.