Acts 1:4-5, 8

and, being assembled together with them, he charged them not to depart from Jerusalem, but to wait for the promise of the Father, which, said he, ye heard from me: for John indeed baptized with water; but ye shall be baptized in the Holy Spirit not many days hence.

But ye shall receive power, when the Holy Spirit is come upon you: and ye shall be my witnesses both in Jerusalem, and in all Judæa and Samaria, and unto the uttermost part of the earth.