Which event is NOT considered a key moment in Jesus Christ's life?

The establishment of the church after Jesus' resurrection is indeed a pivotal event in Christianity, marking the beginning of the Christian faith and its spread among followers. This moment highlights the significance of Jesus' teachings and the transformative impact his resurrection had on his disciples and early Christians.

In contrast, the other events—his birth, his crucifixion, and the resurrection itself—are foundational narratives within Christian doctrine that outline crucial aspects of his life and mission. His birth is celebrated as the incarnation of Christ, signifying the arrival of the Messiah. The crucifixion is central to the Christian understanding of atonement and sacrifice.

While the influence of Jesus on the Roman Empire is noteworthy, it does not represent a key moment in his personal life or ministry but rather reflects the broader historical context in which his teachings spread. Thus, the role of Jesus in the Roman Empire is not characterized as a defining event of his life, making it the correct answer to this question.