Saint John of the Cross is a figure of immense significance in the landscape of Spanish mystical literature. Born Juan de Yepes y Álvarez in Fontiveros, Spain, in 1542, John became a Carmelite friar and, later, a major proponent of the Counter-Reformation. He is renowned for his works that fuse spirituality, theology, and poetry, with 'Ascent of Mount Carmel' being amongst his most celebrated treatises. Coupled with its companion piece, 'The Dark Night of the Soul', these writings delve into the peregrination of the soul to its union with God. 'Ascent of Mount Carmel' outlines the spiritual journey through the metaphor of climbing a mountain, representing the rigorous path toward contemplative life through detachment, humility, and suffering. Recognized for the richness of his imaginative style and the depth of his interpretive skill, John's work navigates the intersection of mystical experience and philosophical inquiry, shaping a tradition of mystical theology that reverberates through the subsequent centuries. His influence transgresses the boundaries of religious doctrine, impacting literature and psychology with terms like 'dark night' entering the broader psychological lexicon as a descriptor of spiritual crisis and transformation. Saint John of the Cross was canonized in 1726 and declared a Doctor of the Church in 1926, affirming his profound contribution to Christian mysticism and to the Spanish Golden Age of literature.