A Christian polemicist proved the Trinity by equating divine attributes with persons

Evidence

The author shows a good knowledge of Islam and of the Koran: the Muslim’s letter presents Abraham as the first Muslim; the Christian retorts by saying that Muhammad himself said that he was the first Muslim and provides a citation from the Koran to prove it. He defends the Trinity while affirming God’s unity; far be it from a true Christian to say that “God is the third of three.” Does not God, in the Bible, refer to himself in the plural? God has many attributes, he asserts, two of which are eternal: life and knowledge. Life corresponds to Christ (´, kalima), knowledge to the Holy Spirit (ˆ, rûh); thus the Trinity can be proven from a reflection on God’s nature. — John V. Tolan, Saracens, 388

Categorization

• XREF: The life/knowledge to Christ/Spirit mapping recalls the reader’s knowledge of early Christian Trinitarian theology and Jewish-Christian debates over divine attributes.
• SEED: Essay angle: how interfaith polemic forced Christians to find new arguments for the Trinity — devotional theology produced under pressure of apologetics.