Trinity refers to the teaching that the one God comprises three distinct, eternally co-existing persons: the Father, the Son (incarnate in Jesus Christ), and the Holy Spirit. Together, these three persons are sometimes called the Godhead, although there is no single term in use in Scripture to denote the unified Godhead.

 

       In the words of the Athanasian Creed, an early statement of Christian belief, "the Father is God, the Son is God, and the Holy Spirit is God, and yet there are not three Gods but one God". They are distinct from another: the Father has no source, the Son is begotten of the Father, and the Spirit proceeds from the Father. Though distinct, the three persons cannot be divided from one another in being or in operation. While some Christians also believe that God appeared as the Father in the Old Testament, it is agreed that he appeared as the Son in the New Testament, and will still continue to manifest as the Holy Spirit in the present. But still, God still existed as three persons in each of these times.

 

      However, traditionally there is a belief that it was the Son who appeared in the Old Testament because, for example, when the Trinity is depicted in art, the Son typically has the distinctive appearance, a cruciform halo identifying Christ, and in depictions of the Garden of Eden, this looks forward to an Incarnation yet to occur. In some Early Christian sarcophagi the Logos is distinguished with a beard, "which allows him to appear ancient, even pre-existent.