This is he who came by water and blood, Yeshua the Messiah; not with the water only, but with the water and the blood.
It is the Spirit who bears witness, because the Spirit is the truth.
For there are three who bear witness, the Spirit, and the water, and the blood; and the three agree as one.
If we receive the witness of men, the witness of God is greater; for this is God's testimony which he has testified concerning his Son.
He who believes in the Son of God has the witness in him. He who doesn't believe God has made him a liar, because he has not believed in the testimony that God has given concerning his Son.
The testimony is this, that God gave to us eternal life, and this life is in his Son.
He who has the Son has the life. He who doesn't have God's Son doesn't have the life.