The Acts 1:3-5

to whom also he presented himself living, after he had suffered, with many proofs; being seen by them during forty days, and speaking of the things which concern the kingdom of God; and, being assembled with them, commanded them not to depart from Jerusalem, but to await the promise of the Father, which said he ye have heard of me. For John indeed baptised with water, but ye shall be baptised with the Holy Spirit after now not many days.