LOVE, because the Holy Trinity [God the Father, and God the Son (Jesus Christ), and God the Holy Spirit], is a community of love: three distinct Persons, in one God. Trinity = tri + unity. In the Bible it says that: God is love (1 John 4: 16). I hope this answers your question; and is helpful. Frank
Really, the trinity is not a Bible teaching but existed many years before Christianity came on the scene. The Egyptians, Babylonians were among the first to worship a triad of Gods. The Egyptians for instance worshipped the trinity of Amon-Ra, Ramses II, and Mut. The Encyclopedia of Religion says: "Theologians agree that the New Testament does not contain an explicit doctrine of the Trinity."
Scholars have known for years that the doctrine of the Trinity didn't come on the scene until around 325 CE. This is well after the Bible had been completed and the Christian Congregation was already fully established. Do research on the Council of Nicaea where this doctrine got it's start. Yes, the Trinity is in fact, not a Bible teaching.