Abner of Burgos

Abner of Burgos (c. 1270 – c. 1347), later known as Alfonso of Valladolid or 'Master Alfonso', was a significant figure in medieval Castilian intellectual and religious life. Initially a Jewish philosopher, he converted to Christianity and became a notable polemical writer, dedicating his efforts to critiquing his former religion. His intellectual background was rich, encompassing deep knowledge in Biblical and Talmudical studies, alongside a strong command of Peripatetic philosophy and the practice of astrology. According to his own account in his work *Moreh Zedek/Mostrador de justicia*, a pivotal moment in his life occurred in 1295. This was prompted by his encounter with the distress of Jews involved in a failed messianic movement in Avila. He reported experiencing a 'dream' where crosses appeared on his garments, an event that catalyzed his questioning of Judaism and ultimately led to his conversion. His writings, often critical of Jewish tenets, aimed to provide philosophical and theological arguments supporting Christian doctrines, reflecting his complex intellectual journey and his commitment to his new faith.