Which council affirmed the Trinity and the Divinity of the Holy Spirit?

The Council of Constantinople, convened in 381 AD, played a pivotal role in affirming the doctrine of the Trinity and specifically addressed the divinity of the Holy Spirit. This council built upon the foundation laid by the previous Council of Nicea, which established the full divinity of Jesus Christ. The Council of Constantinople further clarified the relationships within the Trinity, emphasizing that the Holy Spirit is fully divine, co-equal, and co-eternal with the Father and the Son.

This affirmation was crucial in shaping the Nicene Creed, which articulated the belief in the Holy Spirit's divine nature, thus countering various heretical views that diminished the role or status of the Holy Spirit within the Godhead. The emphasis on the Holy Spirit's divinity ensured a more robust and comprehensive understanding of the Trinity as a whole, defining the orthodoxy that has persisted in mainstream Christianity.

The other councils mentioned, while significant in their own rights, focused on different theological issues and did not specifically affirm the Trinity in the same way. For instance, the Council of Nicea dealt primarily with the conflict regarding Arius's views on Christ’s divinity, while the Council of Chalcedon was concerned with Christology and the nature of Christ