In Acts 1:8 Jesus told His disciples that when this filling of the Holy Spirit would occur, they would have power for service, especially to be a witness for Christ. Acts 1:8 says, “But you shall receive power when the Holy Spirit has come upon you; and you shall be witnesses to Me in Jerusalem, and in all Judea and Samaria, and to the end of the earth.” This was the promise that Jesus referred to earlier in His ministry: “Behold, I send the Promise of My Father upon you; but tarry in the city of Jerusalem until you are endued with power from on high” (Luke 24:49).

This help, control, or empowerment was promised also in the Old Testament, where the promise of the Messiah was often linked to the promise of the Holy Spirit. When the New Covenant was foretold in the Old Testament it was often prophesied as a time when the Holy Spirit would be given to all believers in a way that he was not given to all believers under the Old Covenant.

Joel 2:28-29 is one of those passages.

And it shall come to pass afterward that I will pour out My Spirit on all flesh; your sons and your daughters shall prophesy, your old men shall dream dreams, your young men shall see visions. And also on My menservants and on My maidservants I will pour out My Spirit in those days. (Joel 2:28-29)