Oneness is the nature of infinite Spirit, God. Anything other than oneness would divide God's omnipotence and omnipresence—an utter impossibility.
"Do not I fill heaven and earth? saith the Lord" (Jeremiah)
Jer. 23:24 . "Know therefore this day, and consider it in thine heart, that the Lord he is God in heaven above, and upon the earth beneath: there is none else" (Deuteronomy).
Deut. 4:39 .
If God is All, He must be One. Mary Baker Eddy, the Discoverer and Founder of Christian Science, explains, "The allness of Deity is His oneness."
Science and Health with Key to the Scriptures, p. 267 . Christian Science has this logic at its heart, and its entire teaching proceeds from this basis.