The theology of Jesus’ holy Image on the Shroud as the Sign of Jonah is a very recent development. Our Church fathers could not make that connection because the Shroud (Image of Edessa) was not publicly recognized as a burial cloth. Therefore it could not be thought of as the Sign of Jonah. As we know, several legends arose to explain His facial Image (not made by hands), and none of them were true.
In 1357 the Shroud was publicly presented as Jesus’ burial cloth. In 1898 Pia’s astounding negative plate proved that this postulation was correct, but did not prove a miraculous origin of Jesus’ Image. The approbation of “Not made by hands,” while suggesting a supernatural source, also allows for a natural event. Indeed, Vignon’s published research of 1902 dismisses a radiological mechanism for the Image formation by saying that no known way for a human corpse to emit the necessary radiation existed. Vignon postulated a “vapor” theory of Image formation, an idea that has now been shown to be false.
Not until the C-14 dating results of 1988 and their correct interpretation by the Antonacci/Rucker team in 2015 have we known for sure that a miracle was the mechanism by which our Lord’s sacred Image was imprinted onto His burial Shroud. And now that we are sure of that miracle we can make the connection to the ancient Sign of Jonah that Jesus predicted.
Luke 11:29-32 adds an additional element to this marvelous sign: the warning to repent or suffer the consequences of divine destruction. In my opinion, the Sign of Jonah is that warning to this present generation to give up its evil ways, and those evil was are nothing else that our development and deployment of massive instruments of destructive retaliation. Jesus warned us against the philosophy of retaliation, preaching the philosophy of returning good for evil. The Vatican has condemned our MAD protocol as a “negative peace.”
The fulfillments of Luke 12:49 and Luke 21:34-35 are just around the corner and will happen in the 21st century.