Source:  Christian Answers.net

The doctrine of the Trinity — that God the Father, God the Son, and God the Holy Spirit are each equally and eternally the one true God — is admittedly difficult to comprehend, and yet is the very foundation of Christian truth. Although skeptics may ridicule it as a mathematical impossibility, it is nevertheless a basic doctrine of Scripture as well as profoundly realistic in both universal experience and in the scientific understanding of the cosmos. Both Old and New Testaments teach the Unity and the Trinity of the Godhead.

​The idea that there is only one God, who created all things, is repeatedly emphasized in such Scriptures as

Isaiah 45:18: “For thus saith the Lord that created the heavens; God himself that formed the Earth and made it; …I am the Lord; and there is none else.”

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