At its best, theology is like holding a jewel up to the light and being exhilarated by the beauty of the facets that are reflected.
An analogy which I have found especially helpful in understanding the role of theology is that of a glass prism breaking up a beam of white light into the colors of the rainbow—red, orange, yellow, green, blue, indigo, and violent. All that the prism does is to separate out these colors; they are already present in the beam of white light, but cannot be individually distinguished until the light is passed through the prism.
Theology takes the Christian proclamation of Jesus Christ as Savior and Lord, and identifies the individual themes, ideas and possibilities which are mingled together within this glorious amalgam.
— Alister McGrath, from Knowing Christ, page 160