A week later he heard in the town that Dom Diego de Balthasar had been arrested by the Inquisition for Judaism. The news brought him a more complex thrill than that shock of horror at the treacherous persistence of a pestilent heresy which it excited in the breast of his fellow-citizens. He recalled to mind now that there were thirty-four traces by which the bloodhounds of the Holy Office scented out the secret Jew, and that one of the tests ran: "If he celebrates the Passover by eating bitter herbs and lettuces." But the shudder which the thought of the Jew had once caused him was, to his own surprise, replaced by a secret sympathy. In his slowly-matured, self-evolved scepticism, he had forgotten that a whole race had remained Protestant from the first, rejecting at any and every cost the corner-stone of the Christian scheme. And this race--he remembered suddenly with a leap of the heart and a strange tingling of the blood--had once been his own! The knowledge that had lurked in the background of consciousness, like the exiled memory of an ancient shame, sprang up, strong and assertive. The far-off shadowy figures of those base-born ancestors of his who had prayed in the ancient synagogues in the days before the Great Expulsion, shook off the mists of a hundred years and stood forth solid, heroic, appealing. And then recalling the dearth of bitter herbs in the market-place on what he now understood was the eve of Passover, he had a sudden intuition of a great secret brotherhood of the synagogue ramifying beneath all the outward life of Church and State; of a society honeycombed with Judaism that persisted tenaciously and eternally though persecution and expulsion, not in stray units, such as the Inquisition ferreted out, but in ineradicable communities. It was because the incautious physician had mistaken him for a member of the brotherhood of Israel that he had ventured upon his now transparent jests. "Good God!" thought Da Costa, sickening as he remembered the _auto-da-fé_ he had seen at Lisbon in his boyhood, when De la Asunçao, the Franciscan Jew monk, clothed in the Sanbenito, was solemnly burnt in the presence of the king, the queen, the court, and the mob. "What if 'twas my tale to Frei José that led to Dom Diego's arrest! But no, that were surely evidence too trivial, and ambiguous at the best." And he put the painful suspicion aside and hastened to shut himself up in his study, sending down an excuse to his mother and brother by Pedro, the black slave-boy.