The Westminster Shorter Catechism
Q. 6. How many persons are there in the Godhead?
A. There are three persons in the Godhead: the Father, the Son, and the Holy Ghost; and these three are one God, the same in substance, equal in power and glory.
The Westminster Shorter Catechism in Modern English:
Q.6. How many persons are in the one God?
A. Three persons are in the one God, the Father, the Son, and the Holy Spirit. These three are one God, the same in substance and equal in power and glory.
1. Why has this doctrine given rise to opposition during the history of the Church?
The devil recognises that since the Trinity is a mystery which human reason cannot explain, and since it is the primary object of our faith and worship, it is fertile ground for use as a stumbling block.
2. How important is this doctrine to our faith?
It is essential and vital. Without this doctrine we would not know of the love of the Father, the merit of the Son and the sanctifying influence of the Holy Spirit in the purchase and application of redemption.
3. What is meant by the word "Godhead" in this question?
It means the divine nature that is possessed by all three persons.
4. What denomination denies the doctrine of the Trinity?
The Unitarians deny this doctrine. They teach that there is only one person in the Godhead, the Father, and deny the true deity of Christ and the Holy Spirit.
5. How can one prove that there are three persons in the Godhead?
This can be proved by many teachings in Scripture. It can be proved from the baptismal formula; from the baptism of Christ; from the blessing given by Paul in 2 Cor. 13:14; from John's salutation to the seven churches; from the different tasks attributed to the three persons.
6. Could you give an example of these different tasks?
Yes, 1 Peter 1:2 gives an example of their different tasks in the work of redemption. It speaks of the Father's foreknowledge, the Son's death for His people, and the Spirit's task of sanctification.
7. How is it that all three could be one God?
The doctrine teaches that "God is One in one sense, and Three in a different sense. He is One is substance and Three in persons." (J.G.Vos). The Scriptures assert that the Son and the Holy Ghost are God and are equal with the Father. True, this mystery is difficult to understand. But we now believe it by means of the Word of God and can look forward to enjoy the perfect knowledge of it in heaven.
8. How can we best state the doctrine in simple terms?
One of the best statements is: "There is but one God, the Father and the Son and the Spirit is each God, and the Father and the Son and the Spirit is each a distinct Person ..." (Dr. L. Boettner).