I recently re-read a trio of books by artist Frederick Franck on the topic of drawing as a meditative, spiritual activity: The Zen of Seeing, The Awakened Eye and Art as a Way. I first read them when I was studying art as part of my A-Levels but I seized the chance to return to them after returning to blind drawing at the Oxford Summer School. Franck recommends looking at a subject, then closing your eyes for a few minutes before opening them and putting pen to paper as part of an intensely observational approach to drawing.
They aren’t method books; alongside a little bit of how, there is a lot of why. They are full of references to spirituality, particularly Zen Buddhism (although Jesus gets a few quotes) and produced from hand written rather than typeset pages; however, even if either of those things throw up stumbling blocks, they also have ample drawings to illustrate them. The real thrust of the book is to encourage people to risk being enriched by the experience and actively seeing what is around them.