Prof. Karen King, from Harvard, presented a paper in the Vatican about a new papyrus fragment recently surfaced by an American collector. The small scrap included a fascinating reference by Jesus to his wife, and appeared to say that she was worthy to be a disciple. King, an authority on gnosticism, was inclined to believe it an authentic early account of the life of Jesus, a gospel.

It turned out to be a fraud. Sabar eventually tracks down the con man who created the forgery, and this makes a terrific and surprising detective story. The final chapters try to indict King and Harvard for gullibility, and these are far less convincing. Forgeries happen all the time, and people—even experts—are taken in by them all the time. If they weren’t convincing, they wouldn’t be interesting. Sabar is particularly blind in thinking that a divinity school professor would understand that the sort of sleuthing he undertook is possible: three separate trips to Germany on the trail of the con man’s East German background, extensive public records searches in numerous states, treks through school archives from Berlin to Florida, handwriting experts, archival searches for traces of the porn sites that the con man set up and to which the forgery was a side hustle.

Sabar also persists in misunderstanding King’s argument that the fragment, even though forged, can focus our attention on an underlying truth. We have very little evidence of Jesus’ views on sexuality or on the status of women. What evidence we do possess is chiefly in the letters of a man who disliked sex and who thought that family life was perfectly pointless because the world was going to end in the next year or two. Several of the letters in which Paul discusses this were forgeries.