Ask anyone to describe the shape of a square, and you might expect a variety of explanations that yet have common talking points (for example, 90-degree corners with four equilateral sides). Get one of the defining features of a square wrong, and you're no longer describing a square, regardless of culture, time, or place. Similarly, if a believer were to summarize the gospel, we might reasonably anticipate that each explanation would conform to a particular shape that transcends different communication styles, theological influences, and cultural idioms. In Paul's first letter to the church at Corinth, he provides a particular shape to the gospel of "first importance" (1 Cor. 15:3–4) by forming it around the death, burial, and resurrection of Jesus. He goes on to provide credible eyewitness reports from various sources to validate his claims, including his own testimony (vv. 5–8).