A Jewish man named Nathan traveled to an island and was on the brink of committing a serious sin with a famous courtesan. The room was prepared. The door was closed. He was about to fail.
Then he sat down to undress and his eyes fell on the tzitzit — the fringes attached to the corners of his garment, commanded in Numbers 15:37-41 as a visual memory of the mitzvot. The Torah calls them a sign, twice, in connection with the words I am the Lord your God — a reminder that the same voice rewards and punishes.
Nathan looked at his fringes. He saw God. He stood up and walked out.
The woman was stunned. No man had left her before. She pursued him — not for revenge, but for the answer. Why did you withdraw?
He told her about the fringes. About the verse. About the God who speaks twice in one line because once is not enough. Before leaving, he gave her his name and address in Tiberias.
She sat with what he said. Then she rose and divided her property into three portions — one third to the Roman state in taxes, one third to the poor, and one third she kept and carried with her across the sea.
She came to Tiberias and sought out Rabbi Chiya. She asked to convert. He examined her carefully. Is this about love for one of my students? he asked. She produced the letter Nathan had written her — the one that explained she wished to join Israel for love of the Torah itself, not for love of a man. Chiya accepted her. She lived the rest of her life in purity, a Jew by choice.
Gaster's Exempla (No. 35, 1924) tells it as a story of the tzitzit. But it is also a story of what happens when a mitzvah does its work in two directions at once — saving the Jew from sin, and drawing a stranger toward the covenant.