Nor do we have reliable accounts from later times. What we have are legends, about some of the apostles – chiefly Peter, Paul, Thomas, Andrew, and John. But the apocryphal Acts that tell their stories are indeed highly apocryphal.

— Bart D. Ehrman, "Were the Disciples Martyred for Believing the Resurrection? A Blast From the Past", ehrmanblog.org

Bart Ehrman

— Emerson Green, "Who Would Die for a Lie?", The big problem with this argument [of who would die for a lie] is that it assumes precisely what we don’t know. We don't know how most of the disciples died. The next time someone tells you they were all martyred, ask them how they know. Or better yet, ask them which ancient source they are referring to that says so. The reality is [that] we simply do not have reliable information about what happened to Jesus' disciples after he died. In fact, we scarcely have any information about them while they were still living, nor do we have reliable accounts from later times. What we have are legends.