Alfonso de Spina was a 15th-century Spanish Franciscan friar and theologian known for his contributions to religious literature. He is best recognized for his work titled "Fortalitium Fidei," which defends the Christian faith against heresies and promotes the importance of faith in God. His writings reflect the intellectual climate of the time, addressing various theological issues. De Spina's influence extended beyond his lifetime, as his works were referenced by later scholars and theologians. He was part of the broader movement of the Renaissance, which sought to reconcile faith with reason. His efforts contributed to the ongoing dialogue between Christianity and emerging philosophical ideas.