Original Verse:
John Chapter 15 Verse 27You will also testify, because you have been with me from the beginning.

Reference Verses:
Matthew Chapter 10 Verse 18Yes, and you will be brought before governors and kings for my sake, for a testimony to them and to the nations.
Acts Chapter 1 Verse 8But you will receive power when the Holy Spirit has come upon you. You will be witnesses to me in Jerusalem, in all Judea and Samaria, and to the uttermost parts of the earth."
Luke Chapter 1 Verse 1Since many have undertaken to set in order a narrative concerning those matters which have been fulfilled among us,
Luke Chapter 24 Verse 48You are witnesses of these things.
Acts Chapter 1 Verse 22beginning from the baptism of John, to the day that he was received up from us, of these one must become a witness with us of his resurrection."
Acts Chapter 3 Verse 15and killed the Prince of life, whom God raised from the dead, to which we are witnesses.
Acts Chapter 5 Verse 32We are His witnesses of these things; and so also is the Holy Spirit, whom God has given to those who obey him."
Acts Chapter 10 Verse 41not to all the people, but to witnesses who were chosen before by God, to us, who ate and drank with him after he rose from the dead.
Acts Chapter 13 Verse 31and he was seen for many days by those who came up with him from Galilee to Jerusalem, who are his witnesses to the people.
John Chapter 19 Verse 35He who has seen has testified, and his testimony is true. He knows that he tells the truth, that you may believe.
John Chapter 21 Verse 24This is the disciple who testifies about these things, and wrote these things. We know that his witness is true.
1st John Chapter 1 Verse 2(and the life was revealed, and we have seen, and testify, and declare to you the life, the eternal life, which was with the Father, and was revealed to us);
1st John Chapter 4 Verse 14We have seen and testify that the Father has sent the Son as the Savior of the world.