He told them to wait.
Wait for who?
Every time I read the account of the first Pentecost, I’m struck by the fact that Jesus’ followers had no clear picture of exactly who or what they were waiting for. But the risen Messiah told them to wait, so that’s exactly what they did.
On one occasion, while he was eating with them, he gave them this command: “Do not leave Jerusalem, but wait for the gift my Father promised, which you have heard me speak about. For John baptized with water, but in a few days you will be baptized with the Holy Spirit.” (Acts 1:4-5)