A man lay dying. He had ten sons. His wife, in a bitter moment late in the marriage, had once told him that only one of the ten was biologically his. The other nine were fathered by other men. She had never named which one.
On his deathbed the man faced a terrible choice. He could leave his fortune to all ten and inadvertently reward the nine children of betrayal. He could leave it to none and punish the one who was truly his. Instead, he made a stipulation in the will: my fortune goes to the son who can prove he is mine.
He died. All ten sons contested the will. Each one claimed to be the real son. A judge was appointed to decide. He had no biological test available in the ancient world. He had to construct one.
The judge gave his verdict. Bring the dead man's body to the courtroom, he ordered. Each of you will take a cudgel. Walk up to his corpse and beat it. Whichever of you strikes hardest proves your claim, because only a true son will fight most fiercely for his inheritance.
Nine sons stepped forward and struck the body, some halfheartedly, some with real force. The tenth son stood frozen, then dropped his cudgel on the floor. I will not do it, he said. Whatever my father said about me in his will, whatever my mother claimed, I will not beat the body of the man who raised me.
The judge rose. You are the son, he announced. The test was never to find the strongest beater. A son's body rebels at striking his father even to win a fortune. The other nine have just proven they are not sons.
This story from The Exempla of the Rabbis (Gaster, 1924), drawn from Codex Gaster 185, is an old Jewish variant of a tale known in many cultures. It teaches that honor for a parent is not tested by loyalty oaths. It is tested by whether you can raise a stick against his lifeless body. The true son cannot.