Final answer:
The Nicene Creed was established to resolve the theological debate on the nature of God and to oppose Arianism by affirming the divinity of Jesus Christ as consubstantial with the Father.
Step-by-step explanation:
The Nicene Creed was formulated to address the critical theological issue of Arianism and to affirm the full divinity of Jesus Christ, thus resolving the contentious debate on the nature of God. This Creed articulated that Jesus Christ was 'consubstantial' with the Father, countering the Arians who believed Jesus was a creature made ex nihilo (out of nothing) and thus not divine.
The decisions reached at the Council of Nicea set a doctrinal standard for Christianity, emphasizing the unity and equality of the son with the father, which is foundational to Christian orthodoxy. This clarification of theological doctrine helped establish a specific set of beliefs backed by institutional authority in early Christianity.