For the last few years I've threatened to write a book titled The Jesus I'll Never Know. It would be a response to the tendency in the wider world of U.S. Christianity to personalize the Son of Man—and tame him in the process.

As the vulgar Eric Cartman character of the South Park cartoon memorably put it, Christian tunes often sound like love songs that swap in "Jesus" for "baby." Likewise, in the M. Night Shyamalan movie Wide Awake, Rosie O'Donnell played the role of Sister Terry, a baseball-cap-wearing nun who assigned her young students chapters in the workbook Jesus Is My Buddy as homework.

The point of my book would be that the closer we get to the Gospels, the more we realize that these four witnesses to Jesus' life and ministry intentionally placed some distance between the reader and the wonder-working preacher from Nazareth. Of Jesus' childhood we know little. We get a quick peek at him as a young man, going at it with scribes in the Temple (foreshadowing the fireworks to come); then we see him fully grown, being baptized by John, proclaiming the kingdom of God, teaching, healing, casting out evil spirits, calming stormy waters, and hurtling himself toward his own demise by refusing to make nice with Jerusalem or Rome.

But we don't really "see" Jesus. For some reason—possibly the Jewish prohibition of idolatry—the Gospel writers forgo almost all physical description of him. Whether Jesus towered over the crowd like Saul or could see eye-to-eye with Zacchaeus we know not. And so we guess: The history of Christian iconography attests to the thousands of attempts to give physical expression to this mystery.

One of the many things that I appreciate about Michael J. McClymond's new introduction to scholarly ...