Powell argued that the way to determine which of the three monotheistic faiths (Judaism, Christianity, or Islam) is the right one would be to:

Answer: Demonstrate the authenticity and trustworthiness of the new testament as a reliable account of the person and work of Jesus.

Explanation:

The best way to determine where God's moral law comes from according to Powell is that the moral of God are the opinion of what is right or wrong. To determine the right faith among the 3 monotheistic faiths is to demonstrate the reliability of the account of Jesus Christ in the new testament.

Powell opined that the historical reliability of the Gospels refers to the reliability and authenticity of historic character of the four new testament gospels documented historically. While all four canonical gospels contain sayings and events which may meet the five criteria for historical reliability, the evaluation of these gospel elements is still an ongoing debate. Almost all scholars of antiquity agree that Jesus existed, nonetheless, Scholars vary on the historical documentation that describe the Biblical accounts of Jesus.

Powell argued that the way to determine the right monotheistic faith among Judaism, Christianity, or Islam would be to prove the truthfulness, the origin, the attributions, and foundation of the work of Jesus as recorded in the New Testament.