Scripture-first response
“Elohim is plural, so God is multiple persons.”
When Elohim names Israel’s God, it regularly takes singular verbs and refers to one acting subject. Grammar is determined by usage, not English appearance.
What the objection is claiming
The grammatical form is treated as a numerical count despite singular verbs and pronouns.
Genesis 1:1
In the beginning God created the heaven and the earth.Open full referenceThe Bible begins with one acting subject: God created the heavens and the earth.
How the passages answer it
Hebrew nouns can have forms whose meaning is fixed by agreement and context. Genesis 1:1 uses a singular verb for Elohim. The entire canon repeatedly identifies this God as one and denies any deity beside Him.