It is clear then that Greek religion contained two diverse, even opposite, factors: on the one hand the element of _service_ (θεραπεία), on the other the element of _aversion_[22] (ἀποτροπή). The rites of _service_ were connected by ancient tradition with the Olympians, or as they are sometimes called the Ouranians: the rites of _aversion_ with ghosts, heroes, underworld divinities. The rites of service were of a cheerful and rational character, the rites of aversion gloomy and tending to superstition. The particular characteristics of each set of rites will be discussed more in detail later; for the present it is sufficient to have established the fact that Greek religion for all its superficial serenity had within it and beneath it elements of a darker and deeper significance. So far we have been content with the general statements of Greek writers as to the nature of their national religion, and the evidence of these writers has been remarkably clear. But, in order to form any really just estimate, it is necessary to examine in detail the actual ritual of some at least of the national festivals. To such an examination the next three chapters will be devoted. * * * * * The main result of such an examination, a result which for clearness’ sake may be stated at the outset, is surprising. We shall find a series of festivals which are nominally connected with, or as the handbooks say, ‘celebrated in honour of’ various Olympians; the Diasia in honour of Zeus, the Thargelia of Apollo and Artemis, the Anthesteria of Dionysos. The service of these Olympians we should expect to be of the nature of joyous ‘tendance.’ To our surprise, when the actual rites are examined, we shall find that they have little or nothing to do with the particular Olympian to whom they are supposed to be addressed; that they are rites not in the main of burnt-sacrifice, of joy and feasting and agonistic contests, but rites of a gloomy underworld character, connected mainly with purification and the worship of ghosts. The conclusion is almost forced upon us that we have here a theological stratification, that the rites of the Olympians have been superimposed on another order of worship. The contrast between the two classes of rites is so marked, so sharp, that the unbroken development from one to the other is felt to be almost impossible. To make this clear, before we examine a series of festivals in regular calendar order, one typical case will be taken, the Diasia, the supposed festival of Zeus; and to make the argument intelligible, before the Diasia is examined, a word must be said as to the regular ritual of this particular Olympian. The ritual of the several Olympian deities does not vary in essentials; an instance of sacrifice to Zeus is selected because we are about to examine the Diasia, a festival of Zeus, and thereby uniformity is secured.