In Context

5 Who is he that overcometh the world, but he that believeth that Jesus is the Son of God?

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 testimony, because the Spirit is truth.

7 For there are three that bear testimony in heaven, the Father, the Word, and the Holy Spirit, and these three are one.

8 And there are three that bear testimony on earth, the spirit, and the water, and the blood: and these three agree in one.

9 If we receive the testimony of men, the testimony of God is greater: for this is the testimony of God which he hath testified of his Son.

10 He that believeth on the Son of God hath the witness in himself: he that believeth not God, hath made him a liar, because he hath not believed the testimony that God gave of his Son.

1 John 5:8 in Other Translations