Reference

Acts 1:1-6, 1 Corinthians 2:1-3
THE DEMONSTRATION OF THE SPIRIT'S POWER
"After Jesus' death, He presented himself alive to them in many different settings over a period of forty days. In face-to-face meetings, He talked to them about things concerning the kingdom of God. As they met and ate meals together, He told them that they were on no account to leave Jerusalem but “must wait for what the Father promised: the promise you heard from me. John baptized in water; you will be baptized in the Holy Spirit." Acts 1:2-5