A Spiritual Guide is said to be an intelligence, a method of allowing individuals, (who are caught up in the soap opera of their earthy existence), an understanding and an informational stream that will not only allow them to survive, but to follow the pathway that could be described as the quickest way home.
Guides are believed to come in many shapes and forms, from the physical guide who might be your parents, to the intuitive guide who might be working etherically, astrally or mentally, or even on a soul level. The guide's function is said to learn by the interrelation of experience with the individual whom they have chosen to guide. A guide, therefore, (choosing to manifest more mentally and astrally), might take several lifetimes to guide an individual through the various lessons that need to be learnt in Matter during the process of evolution and during the process that the contractual pattern has brought, usually by ties of love. Since there are millions of sub-planes and planes on the inner planes, it therefore follows that there are many different types of guides, some very evolved and some not so. Simply because an individual doesn't wear a physical overcoat it doesn't always mean that they are evolved, even though they might maintain that they are.
Guides are said to have to be trained, they don't suddenly manifest the experiences that are possibly necessary to guide the individual. Therefore more experienced guides will take under their wings less experienced guides and so you have on the inner planes what you have on the outer, that is apprenticeships. As the individual physically down here evolves and has a capacity to handle and hold more energy, so they will attract more evolved guides that will allow them to participate in a richer ritual that life then brings. In a planetary sense, this is the spiritual hierarchy in his many forms, and since time is on one level an illusion, (particularly as you leave the third dimension), it therefore follows that you have a spiritual hierarchy of the past, the future and the present, and the spiritual hierarchy of other solar systems as well as our own.