What are these ingredients? First, the Bible talks about God. The Jews were monotheists, that means, they believed in only one God. The God of the Bible is that One God. The statement in Deuteronomy 6:4 expresses this very well: "Israel, remember this! The Lord - and the Lord alone - is our God."

The early Christians were Jews, and therefore they believed in this one God. When Jesus came into the scene, not only before his death, but specially after his being raised from death, the early Christians began to understand him as divine, and to accord him the honor that they accorded only to God. In Matthew 28.17, it is said that the disciples worshipped Jesus; before this, of course, they only worshipped the one God. Many Scripture references refer to the divinity of Jesus Christ. A few examples:

Titus 2:13: "…our great God and Savior Jesus Christ."

Hebrews 1:8: 'About the Son, however, God said: ''Your kingdom, O God, will last forever and ever!' "

John 20:28: Thomas addresses Jesus as "My Lord and my God."

The thing is the early Christians had no difficulty acknowledging and proclaiming the divinity of Jesus Christ despite their faith in the one God.

Then a third development. Jesus ascends to heaven, so that he is no longer present among his disciples. But the early Christians did not feel the absence of God or of Jesus Christ; instead they felt God truly present with them. This was so because they were conscious of the presence among them of the Holy Spirit, the one Jesus promised to them as the Comforter, the Advocate, the Sustainer, the Enabler.

The early Christians did not, of course, define in detail the relationship between these three entities. Nevertheless, they put these three together. So in many writings in the New Testament, there is mention of God, of Jesus Christ, and of the Holy Spirit. Some examples:

1 Peter 1:2: "You were chosen according to the purpose of God the Father and were made a holy people by his Spirit, to obey Jesus Christ and be purified by his blood. May grace and peace be yours in full measure."

2 Corinthians 13:13: "The grace of the Lord Jesus Christ, the love of God, and the fellowship of the Holy Spirit be with you all."

Matthew 28:19: "Go, then, to all peoples everywhere and make them my disciples: baptize them in the name of the Father, the Son, and the Holy Spirit…"

It was only later on that church councils defined more closely the relationship between Father, Son and Holy Spirit. An example of such a formulation is the Apostles' Creed, which mentions faith in God, the Father Almighty, faith in Jesus Christ, God's only Son, our Lord, and faith in the Holy Spirit.

In summary then, the doctrine of the Trinity is not a biblical doctrine, if we mean by biblical doctrine something that the Bible speaks directly about. But the doctrine of the Trinity is a biblical doctrine in the sense that that doctrine expresses in a formal way the biblical understanding of God as Creator, as Savior, and as Enabler.