The Bible teaches that God is one in substance and three in person - the Father, the Son and the Holy Spirit. Although the Trinity is clearly taught in Scripture it has been attacked throughout church history, and a great many Christians today have never studied it at all.

R. C. Sproul explains the doctrine carefully and clears away the misconceptions that attach themselves to it. While the Trinity is mysterious, he insists, it is not contradictory, and it is essential to understanding the nature of God. One of the Crucial Questions booklets, and a good place to send someone who has been asking.