From the book The Ascent of Mount Carmel by St. John of the Cross which can be found in text or audio.
Book III, The Active Night, Chapter Chapter XLI, Other Motives of Prayer
In The Ascent of Mount Carmel, Book III, Chapter XLI, St. John of the Cross reflects on prayer's higher motives, emphasizing detachment from personal desires and spiritual consolations. He teaches that true prayer seeks union with God, requiring abandonment of self-interest and a focus on God’s will rather than personal satisfaction or feelings of devotion. St. John warns against seeking spiritual experiences for their own sake, as this can lead to pride or distraction. Instead, he urges a humble, selfless approach, rooted in faith, hope, and love, to foster a deeper, more authentic relationship with God.