Divine reality presents itself to us under two guises and both are equally true. Inevitably most spiritual approaches tend to emphasise one more than the other but if we neglect or undervalue either of them we cannot have the other properly because both are essential parts of the whole and each is incomplete alone. No genuine spiritual path will ignore the fact that God appears to us in dual aspect. If it does then it is unbalanced and built on shaky foundations. It will not even have a correct understanding of the principle on which it focuses because, if your perception is unclouded, you will see that each necessarily suggests the other just as a man suggests a woman and vice versa. If you do not see this, you do not see clearly and so, even what you do see, you see through a veil.
The two faces of God are the Transcendent and the Immanent. God Without as Divine Object and God Within as Divine Subject. We can express these two poles in other ways and, as it may help to give a fuller understanding of them, let us do that. First, though, we should say that this duality is somewhat different to the Yin/Yang one even though there are similarities. The duality of Yin and Yang (dark/light, earth/heaven, sustaining/creative, cold/heat and so on) might be conceived as a horizontal complementarity whereas the Transcendent and Immanent duality is more accurately thought of as vertical. It is part of the inexhaustible richness of Creation that it can be viewed in diverse ways and described in diverse terms, all of which are true in themselves but none of which is the whole truth. This is why we can have different religions focusing on different aspects of the whole. Religions all point to the same truth but they come at it from different angles and their perspective is not quite the same.
The Transcendent is God above, the infinitely great and remote. It is Majesty and Law. We respond to it with awe and reverence. We approach it with prayer. The Immanent is God within, the nearest and most intimate. It is the still, small voice. We respond to it as our very self. We approach it through meditation. In one way, the Transcendent God is the object of worship for followers of exoteric religion while mystics seek the Immanent Self and, in that sense, the Immanent is the higher path. However the true spiritual aspirant pays attention to both aspects of God for the simple reason that both are there and neither one is more real or more true than the other. Too much focus on the transcendent, which was the error of the past in the Western world, might lead to authoritarianism and a denial of our own divine nature. Too much focus on the immanent can result in spiritual narcissism, a loss of objectivity and a forgetting that manifestation is hierarchical in structure. A contemporary problem is precisely that many people see spirituality in terms of a deification of their own self. If you take the Transcendent God out of the equation that is a real possibility unless there is a strong external order, such as the Buddhist Sangha, to set down guidelines and control excesses. But, if you forget that the Kingdom of Heaven is within, you risk setting an unbridgeable gulf between Creator and created. God will always remain on the outside and you will never discover what you really are.
So, to those embarking on the spiritual path, I would say be aware of both aspects of the divine. An exclusive focus on either one of them will leave your spiritual development unbalanced, which is not to deny that at certain periods we will legitimately have a predominating focus on a particular aspect, usually the immanent for those aspiring to the mystical path. But never forget the complementary face of God. Due and proper attention to each one will help to develop qualities essential for final attainment, which could be expressed as a state of perfect balance. Neglect of either will leave you falling short. I do not dispute for a moment that, to the liberated soul, the Transcendent God and the Immanent God are one and the same, but you cannot achieve that non-dualistic union of opposites without fully acknowledging them both.