What was the primary outcome of the Council of Chalcedon?

The primary outcome of the Council of Chalcedon, which took place in 451 AD, was the condemnation of Monophysitism. This council was a significant event in the history of Christianity, primarily because it addressed the Christological controversies that had arisen regarding the nature of Christ. Monophysitism was the belief that Christ had a single divine nature, as opposed to having both a divine and a human nature, which was the position upheld by the Chalcedonian Definition.

The Council of Chalcedon asserted that Jesus is both fully divine and fully human in two distinct natures, united in one person without confusion or change. This definition was critical in shaping orthodox Christian beliefs and became a cornerstone in subsequent theological debates. As a result, the rejection of Monophysitism helped to clarify and solidify the understanding of Christ's nature within mainstream Christianity.

The other choices address important theological concepts and events, but they do not encapsulate the primary outcome of that specific council. The establishment of the doctrine of the Trinity occurred earlier, the reaffirmation of apostolic teachings was a broader concern throughout early Christianity, and the focus on papal authority became more prominent in later developments of the church.