John 21:24
This is the disciple who testifies of these things and has written them; and we know that his testimony is true.
John 19:35
He who saw has testified, and his testimony is true, for he knows that he says what is true, that you also may believe.
3 John 1:12
Testimony is borne to Demetrius by all, and by the truth itself; and we also testify, and you know that our testimony is true.
John 15:27
and you shall also testify, because you have been with me from the beginning.
1 John 1:1-2
THAT which was from the beginning, that which we have heard, that which we have seen with our eyes, that which we beheld and our hands felt, concerning the Word of life,??2 and the life was made manifest, and we have seen, and testify, and declare to you the eternal life, which was with the Father, and was manifested to us,??3 that which we have seen and heard, we declare to you, that you also may have fellowship with us. And our fellowship is with the Father and with his Son Jesus Christ.
1 John 5:6
This is he that came by water and blood, Jesus, the Christ; not by water only, but by water and by blood; and the Spirit is that which testifies, for the Spirit is the truth.