Luke 24:48

⁴⁶ And said unto them, Thus it is written, and thus it behoved Christ to suffer, and to rise from the dead the third day:

⁴⁷ And that repentance and remission of sins should be preached in his name among all nations, beginning at Jerusalem.

And ye are witnesses of these things.

⁴⁹ And, behold, I send the promise of my Father upon you: but tarry ye in the city of Jerusalem, until ye be endued with power from on high.

⁵⁰ And he led them out as far as to Bethany, and he lifted up his hands, and blessed them.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

Acts 13:31
And he was seen many days of them which came up with him from Galilee to Jerusalem, who are his witnesses unto the people.
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Acts 2:32
This Jesus hath God raised up, whereof we all are witnesses.
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Acts 1:8
But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judæa, and in Samaria, and unto the uttermost part of the earth.
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Acts 5:32
And we are his witnesses of these things; and so is also the Holy Ghost, whom God hath given to them that obey him.
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Acts 10:41
Not to all the people, but unto witnesses chosen before of God, even to us, who did eat and drink with him after he rose from the dead.
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Acts 1:22
Beginning from the baptism of John, unto that same day that he was taken up from us, must one be ordained to be a witness with us of his resurrection.
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Acts 3:15
And killed the Prince of life, whom God hath raised from the dead; whereof we are witnesses.
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Acts 10:39
And we are witnesses of all things which he did both in the land of the Jews, and in Jerusalem; whom they slew and hanged on a tree:
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