Spiritual involves a realm. A place of existence which isn't earthly.
Attempting to describe the infinite and omnipresent Deity as being in a specific location is, at the very least, a contradiction in terms.
When I confess that Jesus Christ ascended and is seated at the right hand of the Father I do not mean that Jesus sits in a chair somewhere; but that He has received all authority and power. Though this is also an issue that divides Calvinists and Lutherans; namely Lutherans do not "locate" Jesus; so when we confess that we receive the true body and true blood of Christ we accept that the Incarnate Lord Jesus is unconstrained, He does not "leave" His place at the right hand of God to become present in the Eucharist; but rather is equally present wherever He says He will be present.
There is no "where" that I can point to as God being, God is everywhere. There are places, things, where I can confess God has said He specifically acts in special ways, namely in Word and Sacrament, but God is not found "somewhere out there" that is an intensely shallow and, quite frankly, heterodox view of God.
I additionally wouldn't know what a "spiritual realm" is, that language seems rather foreign to the biblical view of things and the historic teachings of the Church; in traditional Christian teaching the material and the spiritual are not separate "worlds" or "spheres" so much as different aspects of creation. There are visible things and invisible things. Hence we say there is one God, the Father Almighty, Maker of all things, both visible and invisible. The human being is not a spiritual thing hidden in a material thing, but instead a human person. The soul is not a ghost dormant within the flesh, but rather the flesh is alive and animated by the soul: we are not enfleshed souls, we are ensouled bodies.
God is not in this or that realm, God is the God of all creation who is beyond all things and in all things; the simultaneously transcendent and immanent. God is not "a spirit" as some might entertain, God is
God. God is therefore fundamentally other than all things, whether material or spiritual, visible or invisible. And He remains entirely throughout all things, both things visible and invisible. Being
other than all these things, and being
present throughout all these things.
-CryptoLutheran