The differentiating factor between religion and magick seems to be whether or not there was a specialist assigned the role as intercessor to the Gods or Elemental Energies. This is also one of the key issues in present day witchcraft - whether or not each person is a direct link to the energy and can meet their needs without assistance, or if we need those persons who have the time, talents, interest, etc. in being a full-time conduit between these energies and those who consider themselves as Pagans, Witches, Wiccans, etc.
While the jury is still out, the majority of Witches think it would be a travesty if we allowed any third party interpretation or mandatory access to that natural energy we are all heir to as humans and part of the interactive Sacred Play that is Gaia, our world and our spiritual world. Many early religions that began as a one-on-one link with the divine later came to a formal, procedurally bound, mockery of our Divine nature. The power in paganism is that we claim our power by right, and will never give or dilute it by channeling it through others. We are as much a mirror of the Gods, as they are a reflection of us.
The nature of deity is that we have created a personalized representation of those forces which are awe-inspiring and important to us, and given them characteristics and names so that we may refer to them amongst ourselves handily. Those outside this rich interactive style came to believe that these forces were indeed outside of us, and labeled them as transcendent, or other. As Luke was taught by Obi Wan and Yoda, there is a life-force which all beings naturally have. We are part of it, have need of it, and can learn to listen and use it. Only recently did we forget as a race, that it is our birthright and the nature of our being. Life, death, rebirth, creation, beauty - these are all a natural use of the energy so readily available.
Books You Might Enjoy:
William Butler Yeats - The Secret Rose And Rosa Alchemica
Henry Cornelius Agrippa - Occult Philosophy And Magick Book Iii
Peter De Abano - Heptameron Or Magical Elements
Parker Torrence - The Craft Grimoire Of Eclectic Magic
Michael Ford - Luciferian Sorcery Luciferian And Sethanic Magick