If “God” is a Trinity, where in the Bible does the word “God” refer to the Trinity?

Nowhere is God referred to as a trinity or a three-in-one God. No-one viewed him as three persons in one God. The concept of the Trinity doctrine is not found in the Bible. Nowhere is God described as a Trinity. The Hebrew word “elohim” is used for God and it is plural but it is the plural of majesty. It still refers to only one person, one God. Jesus Christ had a prehuman existence as a mighty spirit person created by God but he was never God. The expression “God the Son” is not in the Bible. Jesus never said “I am God”, and neither did he hint at it anywhere. So God is not a trinity.