Seeing Is Believing: Experience Jesus through Imaginative Prayer by Dr. Greg Boyd takes a look at Cataphatic, or imaginative prayer as advocated by many in Church Tradition, such as St. Ignatius, the founder of the Jesuit Order.
Boyd's argument is that many Christians struggle with faith because if they are joyless or unsucessful in not sinning in particular ways, the clergy often responds with a 'try harder' response. Since a Christian ought to be joyful, if you are not joyful then you're just not exerting enough effort.
What this results in is Christians hiding struggles from one another and putting on a guise of holiness while often feeling empty inside.
Rather, we ought to seek Jesus and just be honest with Him in our struggles. The process of "Resting in Christ," as defined by Boyd is that we use our imaginations to vividly conceptualize Christ and just exist with Him, that a common understanding of how much He cares for us and wants us to be aware of that becomes evident. Only then might our Christian walk be advanced to its biblical prescriptions.
Obviously, there are objections to this process. One must not give up on 'trying' altogether, but rather an understanding that trying alone will not accomplish much of lasting value. The idea of envisioning Jesus may seem like make-believe, but Boyd argues that this has more to do with our Western science-based culture defining anything non-physical as not real.
Other issues are addressed in the book, along with several stories of people who have undergone dramatic benefits from the process.
So read it with an open mind. As CS Lewis noted in one of his books - if it's useful to you, use it, if not, don't give it a second thought.