There are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one. 1 John 5:7
This is the clearest, and pretty much the only, expression of the Trinitarian concept in the Bible. It is not, however, found in the earliest Greek manuscripts and is omitted from most modern translations. Here, for example, are verses 7-8 in the New Revised Standard Version: "There are three that testify: the Spirit and the water and the blood, and these three agree."
