Everything is energy. This isn't a startling revelation. We are energy fields within a larger energy field. Because we are part of the One energetic Source, our prayers (and thoughts and wishes and feelings and attitudes) make a difference. To hope, to imagine, to care, to plan...it can all be very powerful.
If the energy of life were a pond, then our every move would cause ripples in the pond. Some movements would be larger or more focused than others and would therefore cause bigger ripples (sometimes even waves), but every movement would cause movement within the pond.
Well, life is like a pond in which we "live and move and have our being," but instead of being filled with water this pond is filled with eternal, indestructible energy that has always existed, always will, and is constantly moving into and out of form. So, our thoughts, aspirations, intentions, and choices all cause ripples (and sometimes waves) within this energy pond. When we pray for gay and lesbian Jamaicans to be safe in their country, our prayers are rippling throughout the Universe and will create some kind of change. When we pray for peace in the middle east, the ripples go out. When we pray for a cure for AIDS or Alzheimer's or MS, the ripples go out. When we pray for anything, we know currents of life-energy are flowing to that situation, directed by our intentional prayers. So keep praying. Everything is energy and prayer is a way of directing energy toward accomplishment. Imagine the best, believe in possibilities, and know the energy of life is moving as directed by our prayers.