Trinity

[McCulloch]

Trinity - The Christian doctrine that there is only one God in existence and that He consists of three separate and ontologically divine persons. CHRISTIAN APOLOGETICS & RESEARCH MINISTRY

Trinity (belief in three persons within a single deity; a version of monotheism). Religious Tolerance

Trinity: Three separate Gods. These three Gods are: God the Father, God the Son, and God the Holy Ghost. They are one in purpose and unity. But they are not one in nature (see Godhead). Defining Mormon Terms

trinitarian theology - Creation, Incarnation, Sanctification.
That part of theology that attempts to understand the central Christian mystery of one God in three distinct persons-Father, Son, and Holy Spirit.
trinity - God in three persons-Father, Son, and Holy Spirit. TheoGlossary
A Glossary of Words and Theological Terms

Trinity : God the father, Jesus Christ the son and the Holy Spirit, who continues Christ's work after his death.ethnicity online

Trinity: The mystery of one God in three Persons: Father, Son, and Holy Spirit. The revealed truth of the Holy Trinity is at the very root of the Church's living faith as expressed in the Creed. The mystery of the Trinity in itself is inaccessible to the human mind and is the object of faith only because it was revealed by Jesus Christ, the divine Son of the eternal Father. DICTIONARY OF CATHOLIC TERMS

Trinity The one God in the three parts; God as Father, Son and Holy Spirit. A glossary of Christian terms

Trinity - The doctrine of the trinity is a reference to the "tri-unity" of God. There is only one God, but this God is a unity of one (Deu 6:4; Isa 44:6-8; 45:5-6; 1 Tim 2:5; 1 Cor 8:4). This God is also a complexity within unity (Gen 2:24; 11:6; 1 Cor 3:6-8). The following statements attempt to express both these concepts:
"We worship one God in trinity, trinity in unity, neither confounding the persons nor dividing the substance." (Athanasian Creed)
"God is one in His essential being, but the divine essence exists in three persons; yet in such a way that the divine essence is wholly in each person." (from "New Bible Dictionary" [Revised], J.D. Douglas, ed.)
"In the unity of the Godhead there are three persons; God the Father, God the Son, and God the Holy Spirit. These three are of one substance, co-equal, and co-eternal. (adapted from the "The Westminister Confession")

"We worship one God in trinity, trinity in unity, neither confounding the persons nor dividing the substance." (Athanasian Creed) THEOLOGICAL TERMS & DEFINITIONS

Trinity - a fundamental symbol of the Christian faith and a very important doctrine in catholic Christianity; the Trinity - refers to the oneness and essential unity of God as Father, Son, and Holy Spirit. Trinity Episcopal "Old Swedes" Church

Trinity - "tri" + "unity"
Term not found in the Bible which attempts to provide a label for the concept of ONE GOD in THREE PERSONS (Father Son Holy Spirit.) MinistryServer.com

[Hugh]

Trinity - is trying to dig small hole on the beach so that all the water in the ocean can be confine on it.

[john_anthony_gonzalez]

good summary

[Openmind]

Have you guys ever heard of George Orwell's 1984? More particularly, doublethink? It is the art of holding two (or in this case three) mutually opposing/contradictory ideas in your mind and simultaneously believing them all to be true. This is how one can understand the Trinity. God is one, but he is three. Jesus is 100% man, but he is also 100% God, (or, in fact, 50% God and 50% Holy Spirit). Even though that is 200%, it is still possible.

It becomes easier with time, and indoctrination.