Is God three people or one person? The bible says God is one (Deut 6:4). Yet the Gospels suggest Jesus claimed to be God in the flesh. John 1:1-14 says, in the beginning, was the Word, and the Word with was God and was God and the Word became flesh as Jesus. Matthew 1:23 quotes from Isa 7:14 and Isa 8:8-10 saying that a virgin will conceive a child and his name with being Immanuel (God with us). Daniel 7:13 alludes to a messianic king called the “Son of Man”, that goes into God’s space and rules the world. Lastly, Jesus refers to himself as the Son of Man in many places like in Luke 5:24, where he shows that like God the Father, has the authority to forgive sins. The Holy Spirit that came upon Jesus (John 1:32-34) will be given to us (John 14:16-17), and the Holy Spirit is God’s presence from the Tabernacle/Temple in the old covenant. The concept of Oneness vs Trinity is debated all the time because it goes beyond our comprehension.
I believe God is one but some aspects of him are stretched out and expressed in new ways. They all operate in harmony as one but can be three presentations. Whether you believe they are the same being expressed in three modes, or three separate individuals, they never conflict or contradict one another, and are in perfect harmony. Trinity seems to mean they are separate individuals in a group of three, rather than one being, whereas Oneness or Triune means that it’s all one God operating in three states. A common verse for the view that they are the same is John 1:1. The word was God and the Word was with God. That however presents a paradox, how can the word be with God and be God at the same time? This is what makes the subject seem complicated.
Some say Jesus was the word in the beginning, but he only became the son when he was born as a human. Therefore the word is inseparable from God before Jesus was born and then when he came he was Immanuel (“God with us”). One question that comes from this is, can we observe the Son of God in the old testament besides in prophecy? It doesn’t seem like it so the idea that the son only existed after being born seems to hold up. There’s no sinless human in the old testament, so we don’t see God the Son manifest in the old testament exactly. There are theories about Melchizedek but those are based on Apocrypha and not what the actual Torah teaches. The son was born in the first century, so that is the beginning of the son on earth as a separate person.
Whenever we see visions of God’s throne we don’t see his son seated at his right hand, outside of prophecy. Meaning before Jesus was born God never became the son, which means the only way for John 1:1 to be true is if they are one and the same, rather than two separate individuals. Immanuel, the title Jesus had before he was born means God with us (Matt 1:22-23). John 10:30, says “father and I are one”. So it seems consistent with John 1:1, which goes along with the Oneness view. Others say they are separate because John also says the word was “with” God in John 1:1 and they will argue that the statement, “father and I are one”, is comparable to a married couple “being one flesh”, even though they are two individuals.
The stronger argument overall in my opinion is with a singular Triune God. Some scriptures to ponder: Jesus is the father, son, and spirit according to John 14:8-20. John 14:7-13 alludes to Jesus as the father. John 14:16-20 alludes to Jesus as the holy spirit. In chapter 14 of John, Jesus said the Father was going to send the Comforter, but then in chapter 16, Jesus said that He Himself is going to send the Comforter? Did Jesus lie? No, because Jesus and the Father are one. This is consistent with John 1:33 which has God saying, ‘The one on whom you see the Spirit descend and rest is the one who will baptize with the Holy Spirit.’ Jesus sends the Comforter because He’s the one who “baptizes us with the Holy Ghost.”
Just because they are one doesn’t mean they are doing the same thing at the exact same time, these different presentations of God all have different functions. It is possible for the Father to withhold knowledge from the Son and the Spirit. In Matt 24:36 when asked about his future return Jesus said that no man, nor angel, nor even the son of God knows this information, but only the Father. It makes sense for this information to be kept with the Father since only Son and the Spirit interact with humans directly and the Spirit currently shares God’s knowledge with his people. So the Father has to keep it locked up so that the people won’t know until the appointed time.
One way I think of it is that God is like water. Water can exist in 3 states, solid, liquid, and gas. If you have a sealed container of liquid water and you heat it up or freeze it, at certain temperatures the water will change to vapor or ice respectively. So who is to say God can’t change states and still be the same one, God? Water can’t be in multiple states at the same time, nor can most things on our level of existence. However, since God is often described as omnipresent, then God can be in all three states at once in all places (micro and macro levels) and all-time (past present, and future), since space/time is connected according to Einstein’s Theory of Relativity. Superposition is a reference to quantum (sub-atomic) particles being in multiple different states at once, so maybe this is a reflection of how God operates. Another example is wave-particle duality, which is when a particle can function as a wave, and still be counted as a particle at the same time. Therefore there is nothing that prohibits God from being in multiple places at once functioning as the father, son, and spirit at the same time. Our human thinking is limited to our understanding of reality, God himself can operate as the father, son, and holy spirit, because he can occupy all of space and time..