Christianity has always recognised the existence of three worlds, or regions, through which a man passes; first, the physical world; secondly, an intermediate state into which he passes at death; thirdly, the heavenly world. These three worlds are universally believed in by educated Christians; only the uninstructed imagine that a man passes from his death-bed into the final state of beatitude. But there is some difference of opinion as to the nature of the intermediate world. The Roman Catholic names it Purgatory, and believes that every soul passes into it, save that of the Saint, the man who has reached perfection, or that of a man who has died in "mortal sin." The great mass of humanity pass into a purifying region, wherein a man remains for a period varying in length according to the sins he has committed, only passing out of it into the heavenly world when he has become pure. The various communities that are called Protestant vary in their teachings as to details, and mostly repudiate the idea of _post mortem_ purification; but they agree broadly that there is an intermediate state, sometimes spoken of as "Paradise," or as a "waiting period." The heavenly world is almost universally, in modern Christendom, regarded as a final state, with no very definite or general idea as to its nature, or as to the progress or stationary condition of those attaining to it. In early Christianity this heaven was considered to be, as it really is, a stage in the progress of the soul, re-incarnation in one form or another, the pre-existence of the soul, being then very generally taught. The result was, of course, that the heavenly state was a temporary condition, though often a very prolonged one, lasting for "an age"--as stated in the Greek of the New Testament, the age being ended by the return of the man for the next stage of his continuing life and progress--and not "everlasting," as in the mistranslation of the English authorised version.[248] In order to complete the outline necessary for the understanding of the Resurrection and Ascension, we must see how these various bodies are developed in the higher evolution. The physical body is in a constant state of flux, its minute particles being continually renewed, so that it is ever building; and as it is composed of the food we eat, the liquids we drink, the air we breathe, and particles drawn from our physical surroundings, both people and things, we can steadily purify it, by choosing its materials well, and thus make it an ever purer vehicle through which to act, receptive of subtler vibrations, responsive to purer desires, to nobler and more elevated thoughts. For this reason all who aspired to attain to the Mysteries were subjected to rules of diet, ablution, &c., and were desired to be very careful as to the people with whom they associated, and the places to which they went.