“Therefore know this day, and consider it in your heart, that the LORD Himself is God in heaven above and on the earth beneath; there is no other. (Deut. 4:39)
Unique, an attribute of God; He is the One True God, and the only one. We may never stop to consider how good we have it in this. What if, as we consider in our heart as commanded, there were two gods, equally powerful and immortal? We could wonder the 'what-ifs' to the end of time, but we can see that more than one brings a multitude of problems as any of the pantheons of the ancients showed in many tales. For one thing, every pantheon had division of labor and responsibility. Usually one or two would rebel in some way and anger the big dude or big dudess, kind of like the relationships we have with our brothers and sisters here in the dust. A man might anger any one of the gods and goddesses and have another intervene on his behalf; war among the deities might then cause all manner of havoc for those dwelling below.
Then we come to the Trinity where there is only one God, but yet three. How can this be? We don't know for sure, but we benefit from the loving relationship of the three-in-one. For there is still but one God. The New Testament did not throw out the Old Testament. When God Himself says in Deuteronomy that there is One, then there is One in the Revelation too. I'm not bolstering my argument here; God said it: "There is no other." Which is where we get the concept of the Trinity. As Jesus and the Holy Spirit cannot be other, in which case God would be denying His own statement, they must be God too. How does that work? I don't know; it's above my pay grade.
What I do know is that when Jesus walked this Earth, God was not absent from Heaven. When Jesus breathed His Holy Spirit to the disciples, He did not disappear and God was still present on His throne in Heaven. Jesus forgave sin; that's God's place and prerogative, only God can forgive rebellion against Himself. Therefore Jesus is God. How God does it, I don't know, but He is God and I am not. I know from His word there is no other, and that He is all I need for salvation, sanctification, and justification. I praise God that He is One: the question of two omnipresent gods would pop my little brain circuits.Have a blessed and pleasant day in Christ!