Convert to Christianity; lived in Catalonia in the second half of the fourteenth century. He is believed to have been the son of the astronomer Jacob Poel. In consequence of the persecutions of 1391 he embraced Christianity, assuming the name "Maestre Bonet Bonjorn." He was the intimate friend of Profiat Duran, who had also been compelled to embrace Christianity. Persuaded by David, Profiat consented to accompany him to a foreign country so that they might both return to Judaism. On the eve of departure David changed his mind, and declared himself satisfied with his new religion. Profiat Duran left Spain alone. He subsequently addressed to his friend the well-known epistle "Al Tehi ka-Aboteka," a masterpiece of satirical criticism against converts to Christianity.