But ye shall receive power, when the Holy Ghost is come upon you: and ye shall be witnesses for me, both in Jerusalem, and throughout all Judea, and Samaria, and unto the extremity of the earth.

This very Jesus hath God raised up, of which we all are witnesses.

And we are witnesses of all things which he did both in the region of the Jews, and in Jerusalem; whom they killed suspending him on a tree:

and he was seen many days by those who went up with him from Galilee to Jerusalem, who are his witnesses to the people.

and that repentance and remission of sin should be preached in his name unto all nations, beginning from Jerusalem.

and ye too shall bear your testimony, because ye have been with me from the beginning.

THIS third time I am coming to you: by the mouth of two or three witnesses shall every charge be established.

how shall we escape if we neglect so great salvation, which, commencing at the beginning to be spoken by the Lord, was confirmed unto us by those who had heard him;

And so

But when the Comforter is come, whom I will send unto you from the Father, the Spirit of truth, who proceedeth from the Father, he shall testify of me:

Yet I tell you the truth; It is expedient for you that I go away: for if I went not away, the Comforter would not come to you; but if I go, I will send him unto you.

God superadding his testimony with them, by signs, and wonders, and various miracles, and gifts of the Holy Ghost, according to his own will?

To whom it was revealed, that not for themselves, but for us were their ministrations employed in the things which are now declared unto you by those who have preached the gospel unto you by the Holy Ghost sent down from heaven; on which things the angels bending forwards eagerly desire to gaze.

Whom

And they were all filled with the Holy Ghost, and they began to speak with other tongues, as the Spirit gave them power to express themselves.

While Peter was yet speaking these words, the Holy Ghost fell on all who heard the discourse.

(Now he spake this in reference to the Spirit, which they who believe on him should afterwards receive: for as yet the Holy Ghost was not given; because Jesus was not yet glorified.)

General references

And when they shall bring you before the synagogues, and magistrates, and the ruling powers, be under no anxiety how or what defence ye shall make, or what ye shall say:

And ye are the witnesses of these things.