In depth psychology, the Self is the regulating center of the psyche as opposed to the ego which is the center of consciousness. The Self is also “the central archetype or archetype of wholeness.”  There are many themes and images that refer to the Self: wholeness, union of opposites, the world navel, the transformation of energy, &c. The Self is “the central source of life energy, the fountain of our being which is most simply described as God. Indeed, the richest sources for the phenomenological study of the Self are in the innumerable representations that man has made of the deity.” 
The question is: Is the Self equal to God, thereby placing God inside man’s psyche, or is there a God outside of man’s psyche of which the Self is a symbol or reflection? I shall look at how Jung and several Jungian analysts answer this question.
Jung’s answer is the former but with a qualification. “What one could almost call a systematic blindness is simply the effect of the prejudice that God is outside man. … It would be a regrettable mistake if anybody should take my observations as a kind of proof of the existence of God. They probe only the existence of an archetypal God-image, which to my mind is the most we can assert about God psychologically.”  In other words: “[T]he [S]elf cannot be distinguished from an archetypal God-image” 
Edward F. Edinger agrees but with a slightly different argument: “According to the psychological standpoint man cannot get outside his own psyche. All experience is therefore psychic experience. This means that it is impossible, experientially, to distinguish between God and the God-image in the psyche. My use of the term ‘God’ in this chapter, therefore, always refers to the God-image in the psyche, i.e., the Self.” 
Lionel Corbett is also inconclusive: “[N]uminous experience arises from an autonomous level of the psyche that is either the source of, or the medium for, the transmission of religious experience: empirically we cannot say which.” 
John Dourely , however, taking up Corbett’s argument, does come to a conclusion. In a nutshell, his argument is the following: a) If the psyche is the source of the religious experience then there is no need for a God outside the psyche. b) If the psyche is the medium of the religious experience then the question is, given a God outside the psyche, why would this God resort to “such an ambivalent medium as the unconscious to make his presence and project known to humanity.” [p. 46] If God creates the unconscious as a mediator, Occam’s razor would surely do away with this superfluous entity in favor of the conclusion that the unconscious is the source. “The option for the unconscious as the source of the numinous would lead to the sparse yet organic conception of a wholly intrapsychic transcendence, one that would affirm that the unconscious infinitely transcends ego consciousness but that nothing transcends the total psyche.” [p. 46]
Ann Ulanov  urges caution with these lines of arguments but does so presupposing a God that transcends the psyche. “The fear that meets a psychological approach to theological symbols is that we thereby reduce them to psychological factors. God the Father really comes down to our oedipal complex, writ large. … We talk of ego relating to Self instead of soul to God. God, who transcends creatures and all creation, shrinks to a factor in the human consciousness. The Self may transcend the ego, but does it transcend the psyche?” [p. 63] The upshot of Ulanov’s argument seems to be a hesitation in equating the Self with God because the Self may not transcend the psyche but God certainly does. Furthermore, Edinger’s approach, says Ulanov, of removing the religious traditions from the symbols and looking at them psychologically without the need for doctrines and the religious community leads to a “lonely journey and one in danger of intellectualizing.” [p. 63] Ulanov’s answer also seems to be inconclusive in that she suggests we “look into our own God complex and discern its roots in personal biography, in collective containers, and in core archetypal imagery. Then, and only then, do we come face to face with the big questions, such as: Does this power to create and find images for the center of reality exist within us, or outside us, or both?” [p. 64] However, Ulanov seems to answer this question as she describes the Self’s role as imago Dei and collector of all parts of the psyche, the ego included, into dialogue. In this role, images of the Self “carry into consciousness the Deus absconditus, the God hidden in the unconscious.” [p. 66] God is, therefore, within us. But she also says, “God reaches us through the psyche, that it, too, is part of the flesh in which the Holy incarnates, manifests.” [p. 66] The implication here is that God is also outside us and incarnates within our psyche — were God totally within, there would be no need to incarnate in our psyche as he is already there.
Personally, and at the present moment, what makes sense to me is the approach of Jung/Edinger/Dourley in that I am not positing a God outside the psyche.
I am not, however, addressing myself to the happy possessors of faith, but to those many people for whom the light has gone out, the mystery has faded, and God is dead. For most of them there is no going back, and one does not know either whether going back is always the better way, To gain an understanding of religious matters, probably all that is left us today is the psychological approach. That is why I take these thought-forms that have become historically fixed, try to melt them down again and pour them into moulds of immediate experience. It is certainly a difficult undertaking to discover connecting links between dogma and immediate experience of psychological archetypes, but a study of the natural symbols of the unconscious gives us the necessary raw material. 
Perhaps I have not yet come to the point of asking the “big questions” Ulanov proposes and at that point I may well find that God is outside the psyche as well as within. But, for now, I am exactly as Jung describes: I am not a “happy possessor of faith” and, to me, the God of my youth is dead. The journey I have embarked upon — albeit of no choice of my own — is, indeed, a lonely one as Ulanov suggests, and there is great danger in intellectualizing. The key, I think, is to retain the “experience of psychological archetypes” as the counterbalance to the intellectualizing and to maintain a grounding with another person who can understand the journey as the counterbalance to the danger of becoming identified with the archetypal energies.
 Edinger, E.F., Ego and Archetype, p. 3.
 Edinger, E.F., Ego and Archetype, p. 4.
 Jung, Psychology and Religion, CW 11, par. 100, 102.
 Jung, A Psychological Approach to the Trinity, CW 11, par. 238.
 Edinger, E.F., The Creation of Consciousness, p. 91.
 Corbett, Lionel, The religious function of the psyche, p. 8.
 Dourley, John, “Jung and the Recall of the Gods,” Journal of Jungian Theory and Practice, vol. 8 no. 1 (2006) pp. 43-53.
 Ulanov, Ann, “Theology after Jung,” Journal of Jungian Theory and Practice, vol. 8 no. 1 (2006) pp. 61-68.
 Jung, Psychology and Religion, CW 11, par. 148.