Jesus claimed that he is one with the Father in John 10:30. Does that make him God then?
“I and the Father are one.”
This verse is a favourite with those who teach the Trinity Doctrine. The real question you need to ask yourself is this:
Does being one with something make you that thing? Or does being one with a person make you that person?
The obvious answer is a clear “no”.
If Eve was one with Adam, then that obviously doesn’t mean that she is Adam himself. Rather it means both were in unity as two people. Likewise a husband and wife who are said to be one are two people who are married. It doesn’t make the woman the man or the man the woman. They are still two different people, but are now in unity, a team, or together. While Eve is part of mankind just as Adam was, and us too, being one with Adam never made her Adam himself, and being one with our husband or wife never makes us our partner.
So Jesus being one with the Father or one with God means that he is actually not God because it means that he is the other person in the relationship. It means that Jesus is not the Father, and is not God, but is a different person to God, but is in unity with God. If Jesus were actually God, then you wouldn’t say that “he is one with God”, rather you would say that “he is God”. Simple as that.
Case in hand. Jesus said this in John 17:20-22:
I am not asking on behalf of them alone, but also on behalf of those who will believe in Me through their message, that all of them may be one, as You, Father, are in Me, and I am in You. May they also be in Us, so that the world may believe that You sent Me. I have given them the glory You gave Me, so that they may be one as We are one
John 17 clears this up. The oneness being talked about is unity and we already know that unity with God doesn’t make you God, and that it actually means you are not God. To be one with something means you are not that thing you are one with, but instead, you are unity with. Further, we are invited into this oneness and clearly we are not God. Each one of us should be one with God like Jesus is one with God. We should also be one with Jesus, and the brethren too.
Finally, when Jesus said “I and the Father are one”, he preceded those words with this in verse 29:
“My Father who has given them to Me is greater than all.”
Clearly, the Father is the greatest, even greater than the son. He is the greatest because he is God of all. He is even God to his son, Jesus Christ. He is the Father of all including Jesus Christ. Jesus said it himself in John 14:28:
“You heard me say, ‘I am going away and I am coming back to you.’ If you loved me, you would be glad that I am going to the Father, for the Father is greater than I.”