American Standard Version
And he that hath seen hath borne witness, and his witness is true: and he knoweth that he saith true, that ye also may believe.

Berean Study Bible
The one who saw it has testified to this, and his testimony is true. He knows that he is telling the truth, so that you also may believe.

Douay-Rheims Bible
And he that saw it, hath given testimony, and his testimony is true. And he knoweth that he saith true; that you also may believe.

English Revised Version
And he that hath seen hath borne witness, and his witness is true: and he knoweth that he saith true, that ye also may believe.

King James Bible
And he that saw it bare record, and his record is true: and he knoweth that he saith true, that ye might believe.

World English Bible
He who has seen has testified, and his testimony is true. He knows that he tells the truth, that you may believe.

Young's Literal Translation
and he who hath seen hath testified, and his testimony is true, and that one hath known that true things he speaketh, that ye also may believe.

John 19:35 Additional Translations ...