Acts 1:4-8

4and, 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: 5for John indeed baptized with water; but ye shall be baptized in the Holy Spirit not many days hence.

6They therefore, when they were come together, asked him, saying, Lord, dost thou at this time restore the kingdom to Israel? 7And he said unto them, It is not for you to know times or seasons, which the Father hath set within his own authority. 8But 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.