Acts 1:3-5

3 to whom he showed himself alive after his passion, by many arguments, [or provings], appearing to them forty days, and speaking of the realm of God.

4 And he ate with them, and commanded [to them], that they should not depart from Jerusalem, but abide the promise of the Father, which ye heard, he said, by my mouth;

5 for John baptized in water, but ye shall be baptized in the Holy Ghost, after these few days.