There is only one true faith, because faith is truth. Truth cannot be split or cut in half in such a way that part of it heads left and part of it heads right, and maintain its trueness.
In a general sense, faith consists of countless truths. Faith is a combination of truths. Yet in a way the countless truths make one body. In the body of faith, there are truths that constitute its limbs: some make the limbs that are attached to the chest as its arms and hands; others are attached to the pelvis as its legs and feet. Inner truths constitute the head. The first truths derived from those inner truths constitute the sense organs that are in the face.
Inner truths constitute the head because saying “inner” also means higher. In the spiritual world, all things that are deeper within are also higher. This is true of the three heavens that are there.
The soul and life of this body and all its limbs in the Lord God our Savior. This is why Paul calls the church “the body of Christ” and says that people in the church constitute his limbs, depending on the state of their goodwill and faith [Romans 12:4-5; 1 Corinthians 12:12-31].
In the following words Paul also teaches that there is only one true faith:
There is one body and one spirit, one Lord, one faith, one baptism, one God. He gave people the work of the ministry to build the body of Christ until we all come into a unity of faith, the knowledge of the Son of God, and a complete life to the measure of the stature of the fullness of Christ. (Ephesians 4:4-6, 12-13)
As for the one only true faith being a faith in the Lord God our Savior Jesus Christ, this was fully shown above, Sections 337-339.
The true faith exists in people who believe that the Lord is the Son of God, because they also believe that he is God. Faith is not faith if it is not faith in God.
Among all the truths that initiate faith and form it, the belief that the Lord is the Son of God is the first. This is clear from the Lord’s reply to Peter when Peter said, “You are the Christ, the Son of living God.” Jesus said, “You are blessed, Simon. I say to you. on this rock I will build my church, and the gates of hell will not prevail against it” (Matthew 16:16-18). In this passage and elsewhere in the Word, the “rock” means the Lord in his role as divine truth as well as the divine truth that comes from the Lord. The truth that Peter stated is primary–it is the crown from the head and the scepter in the hand of Christ’s body. This is clear from the Lord’s saying that he is going to build his church on that rock and the gates of hell will not prevail against it. The following words in John show the nature of this point of faith: “If any confess that Jesus is the Son of God, God lives in them, and they live in God” (1 John 4:15).
from True Christianity, Section 379
Sections 337-339: Published 12/2/2020-12/4/2020