Is God outside of us and/ or is God within us? This is often framed in terms of transcendent or immanent - but these are freighted terms, and create an either/or dichotomy that cannot be resolved except by 'mystery' formulations.
God is outside us because God is the creator of this world. And God is also within us because we are his children, and inherited divinity from him.
This is not generally accepted in any simple or literal sense by mainstream Christians, because they regard God as transcendent, utterly other, beyond, and qualitatively different from us... outside time, space and creation. Such a God cannot really be within us and also a part of us because so utterly alien from us.
Those who regard God as wholly immanent do not see God as a personal creator. They cannot coherently regard life as meaningful or purposive - things just are.
But if we instead regard time as part of primary reality, then we can understand this in a sequential fashion.
God (Heavenly parents, man and woman - that is persons) is in the universe, which always existed in uncreated form. And this primal reality also contained the primordial Men - some eternal essence distinct from God: these are the Beings.
Thus God is outside of us. God is separate persons from us, God created this world - and we did not.
God created creation (as it were ) around-themselves (and this is continuous); and also took the Beings that are potential God (i.e. primordial men and women) and procreated us into the children of God. Therefore God is now within us; by inheritance.
This is how Jesus could become fully divine, on a par with our Heavenly parents (although still their children, and still living in their creation) and how we too can potentially become fully divine; because God is literally within us.
As Jesus tells us in the Fourth Gospel - we can become full children of God, and have that Life Everlasting. As fully divine; we can then participate in continuing creation - expanding the pre-existent creation by our own unique creativity (that we have by virtue of having been primordially distinct from our Heavenly parents - so we are not merely copies nor combinations of them).
And this is what God wants, more than anything, and is the reason behind creation. So that our Heavenly parents are no longer alone, but surrounded by a divine family of divine children; engaged in the divine work of creation.
And what makes this all fit together, so that creation is a harmony despite being the open-ended work of many and diverse minds, is Love. Love is the primary value and basis of creation.
It is Love that means there is no conflict but instead glorious harmony, between God without and God within.