I have a confession to make. Although I recognized the value of the imagination, for years I was prejudiced against using it in prayer. I considered it something that people who were drawn to Ignatian Spirituality would use, while I was more influenced by the Carmelites and the Desert Fathers. To be honest with you, I even felt that using the imagination was inferior to other forms of prayer. These prejudices were silly and based, in my opinion, on misunderstandings I had about the great contemplative tradition.
As we advance in our prayer lives, it is not as if God turns off a switch and we never use our imagination again. Advances in our prayer life does not mean that we somehow stop being human and suddenly become angels who lack human faculties. Rather, as we grow in intimacy with Jesus Christ, all of our created nature gets take up and transfigured in the light of Christ. This means that we still use our imagination and our discursive reasoning.
However, our prayer life does begin to fluctuate. It can move from resting in the Lord (also called contemplation) to the more active use of the imagination and back again. Growing in prayer means that we feel comfortable adapting our prayer according to the promptings of the Spirit. This means that instead of clinging to our preferred ways of praying, whether they be centering prayer, imaginative prayer, or lectio divina, we are develop an openness and creativity whereby the Spirit prays in us using a variety means.
In this way, prayer no longer becomes confined to set times and set methods. Our spontaneity in the Spirit allows us to pray while watching a movie or in the midst of conversation. It opens us to the indwelling of the Spirit wherever we find ourselves because our prayer is no longer confined by categories, but rather is characterized by a habitual remembrance of God. We nurture set periods of meditation not to narrow our understanding of prayer, but as the means to gain this sensitivity.
Thus the key is to be flexible. I would argue that such flexibility is the true nature of spiritual poverty because instead of clinging to our personal limitations, it gives us the humility to pray as the Spirit prompts.
I once imagined that God was in the Sun. I thought: The Sun is the center of the universe; it cannot be looked at directly, yet it is always there to warm me. Now I know this was my imagination running away with me, but I still see the connection of a loving & awesome God being the center of my life always there giving me mercy.