The Father,the word,and the holy spirit are the three which are in heaven then came to earth for the salvation of man!(1 John 5:6-8). 6 This is he that came by water and blood, even Jesus Christ; not by water only, but by water and blood. And it is the Spirit that beareth witness, because the Spirit is truth.7 For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.8 And there are three that bear witness in earth, the Spirit, and the water, and the blood: and these three agree in one.
When Jesus died His side was pierced by one of the soldiers and by doing so blood and water flowed out to bear record that what He had spoken was true.At His return all shall see Him including the one who pierced Him at the cross!(John 19:33-37), 33 But when they came to Jesus, and saw that he was dead already, they brake not his legs:34 But one of the soldiers with a spear pierced his side, and forthwith came there out blood and water.35 And he that saw it bare record, and his record is true: and he knoweth that he saith true, that ye might believe.36 For these things were done, that the scripture should be fulfilled, A bone of him shall not be broken.37 And again another scripture saith, They shall look on him whom they pierced. (Revelation 1:7-8). 7 Behold, he cometh with clouds; and every eye shall see him, and they also which pierced him: and all kindreds of the earth shall wail because of him. Even so, Amen.8 I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty.
We see the infinite knowledge of God who is all three that bear record in heaven for He is God Almighty maker of heaven and earth!Then became flesh upon earth through His only begotten Son who then returned to heaven only to send His holy spirit to dwell within those who follow the message of His son.BRILLIANT!(John 16:27-28), 27 For the Father himself loveth you, because ye have loved me, and have believed that I came out from God.28 I came forth from the Father, and am come into the world: again, I leave the world, and go to the Father. (John 4:23-24).