At the heart of Christian theology lies a profound and intriguing question: when did Jesus of Nazareth evolve from a charismatic Jewish teacher to the divine Son of God? This inquiry forms the crux of When Did Jesus Become God?, a captivating conversation between Bart Ehrman and Michael Bird, prefaced by Robert Stewart's insightful historiographic introduction. Ehrman posits that Jesus' divinity was not acknowledged during his lifetime, neither by Jesus himself nor his apostles. Instead, it was only after his crucifixion, when the apostles experienced visions and revelations, that they began to perceive Jesus as a godlike figure, sent by God. Over time, the early Christian community gradually solidified its conviction that Jesus was, in fact, "God," initially by claiming his exaltation to divinity and later by seeing him as a preexistent angel incarnate. Bird, however, disagrees, citing alternative historiographic criteria and scriptural interpretations. He argues that Jesus explicitly claimed to be the divine Son during his ministry and that many apostles recognized him as embodying God's authority and essence. According to Bird, Jesus was the preexistent Son of God from the outset, who subsequently became human, fulfilled the role of Israel's Messiah, and was exalted as God the Father's vice-regent. This engaging and accessible dialogue offers a fascinating exploration of the early Christian church's Christology, making it a valuable resource for anyone interested in the evolution of Christian theology.