Even among most groups that deny the Trinity there is little disagreement that there is but only one God. The concept of Monotheism is what drives many who do not understand the Trinity to try and devise their own schemes to reconcile the concept of Monotheism by reasoning away the Trinitarian view of God. Often it is a basic misunderstanding of what the Trinity truly is that leads people to deny it and once it is denied they, due to human pride often, do not want to accept the truth.
The following are examples of verses that speak to the scriptures proclaiming there is only on God:
1) Probably the most used and relevant passage with regards to the concept of one God is the Hebrew Shema ~ Deut 6:4-5
“"Hear, O Israel: The Lord our God, the Lord is one. You shall love the Lord your God with all your heart and with all your soul and with all your might.”
2) Solomon in 1 Kings 8:60 reiterates the idea:
“that all the peoples of the earth may know that the Lord is God; there is no other.”
3) Isaiah speaks to this so that there is no confusion as to there being only one God in Is 45:5-6
"I am the Lord, and there is no other,
besides me there is no God;
I equip you, though you do not know me,
that people may know, from the rising of the sun
and from the west, that there is none besides me;
I am the Lord, and there is no other."
4) Paul speaking on Mars Hill in Acts 17:22-31 speaks to the statue of the unknown God as being the one and only true God. Not that the statue itself was God but that the unknown God, the God they admit they did not know. was the only true God. So Paul was making sure they understood that all they worshipped were indeed not god’s as there was only one God and it was the God they did not know.
5) Paul in 1 Cor 8:4-6 speaks to there only being one God even when all around them much is spoken of there being other gods.
“Therefore, as to the eating of food offered to idols, we know that "an idol has no real existence," and that "there is no God but one." For although there may be so-called gods in heaven or on earth—as indeed there are many "gods" and many "lords"— yet for us there is one God, the Father, from whom are all things and for whom we exist, and one Lord, Jesus Christ, through whom are all things and through whom we exist.”
6) Other places in the NT that refer to there being only one God are: 1 Tim 2:5; Rom 3:30; James 2:19.
“ there is one God, and there is one mediator between God and men, the man Christ Jesus,” ~ 1 Tim 2:5
“since God is one--who will justify the circumcised by faith and the uncircumcised through faith.” ~ Rom 3:30
“You believe that God is one; you do well. Even the demons believe--and shudder!” ~ James 2:19
We should see that there should be little argument that scripture speaks to there being only one God which when seen with all we have already looked speaks loudly that all three persons: The Father, The Son and The Holy Spirit must all be God.
We will look at this last part in the next installment.
Doctrine of the Trinity Series:
Sermon Series on The Doctrine of the Trinity: Part 1 and Part 2
(all verses used are from the ESV unless stated otherwise)