Acts 1:3-5

Young's Literal Translation

³ to whom also he did present himself alive after his suffering, in many certain proofs, through forty days being seen by them, and speaking the things concerning the reign of God.

⁴ And being assembled together with them, he commanded them not to depart from Jerusalem, but to wait for the promise of the Father, which, [saith he,] `Ye did hear of me;

⁵ because John, indeed, baptized with water, and ye shall be baptized with the Holy Spirit -- after not many days.'