Identity and nature. Many are confused about the difference. This might clear it up. You can change your nature, but you are still you. For example, the Son of God was divine, but he emptied himself and came in the flesh. Yet, regardless of nature, he was still the Son of God.
Doctrines like the Trinity define God primarily as divine nature or a substance. Thus the Father is divine, the Son is divine, and the Spirit. So all three must be God. Further, many denominations are based on creeds that go something like this:
God is one God, and exists in the form of three coeternal and consubstantial persons: the Father, the Son (Jesus Christ), and the Holy Spirit. The three persons are distinct, yet are one “substance, essence or nature”…
But scripturally speaking, God is not defined as a substance or by his nature. But by his identity. Yes God has divine nature, but we read in scripture, that many have and will partake in divine nature. So divine nature is not the prerequisite for making a person God. If that was the case, then the sons of God would be God too.
Romans 1:20
For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse.
2 Peter 1:4
Through these he has given us his very great and precious promises, so that through them you may participate in the divine nature, having escaped the corruption in the world caused by evil desires.
Let’s look at another example. We know that Jesus Christ came in the flesh. And we know that the Word became flesh.
2 John 7
For many deceivers have entered into the world who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist
John 1:1-2
In the beginning was the Word, and the Word was with God…
John 1:14
The Word became flesh and made his dwelling among us. We have seen his glory, the glory of the one and only Son, who came from the Father, full of grace and truth.
Can you see how nature doesn’t define the person and that you are still you, even if your nature changes? If Jesus Christ is the divine Word spoken of in John 1:1, then emptying himself and coming in the flesh would mean that he is a completely different person if nature is what defines God.
So why then is God defined as a substance or divine nature in many church creeds? God is a person. He is called HE, HIM. A divine substance that contains multiple persons is not a HE or HIM. The true faith that as been passed down is that God is one. That this God is the Father of the Lord Jesus Christ. That he is our God and the God of Jesus Christ too.
John 17:3
Now this is eternal life: that they may know you, the only true God, and Jesus Christ, whom you have sent.
Ephesians 4:4-6
4 there is one body and one Spirit, just as you were called to one hope when you were called
5 one Lord, one faith, one baptism;
6 one God and Father of all, who is over all and through all and in all.
1 Corinthians 8:5-6
5 For even if there are so-called gods, whether in heaven or on earth (as indeed there are many “gods” and many “lords”),
6 yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things came and through whom we live.
John 20:17
Jesus said, “Do not hold on to me, for I have not yet ascended to the Father. Go instead to my brothers and tell them, ‘I am ascending to my Father and your Father, to my God and your God.’