This Jesus God raised up, and of that we all are witnesses. Being therefore exalted at the right hand of God, and having received from the Father the promise of the Holy Spirit, he has poured out this that you yourselves are seeing and hearing. (Acts 2:32,33 ESV)
The Holy Spirit
What an amazing time to be alive, for the disciples. Gradually increasing their knowledge and understanding of the Messiah, personally. They were comforted by Jesus, counseled by Jesus, taught by Jesus, and guided by Jesus.
And then He told them He would be gone.
I once lost an irreplaceable book. Not only was the book pretty good, but it had notes written in it, and signed by the author himself. Somehow, it the kafuffle of various moves, it became lost. And at times I have missed it, as much as one can miss an inanimate object.
But those disciples… what a loss Jesus’ death was for them.
They probably had come to understand the salvific necessity of the Messiah’s death. They might have known from the beginning that the physical blessing of being in HIS presence would cease someday. But now He was gone.
Jesus promised His disciples a comforter, counselor, teacher, and guide (John 14:26). Someone who would take His place in their lives.
Yes, they would be with Him in paradise. But the second person of the Trinity, in conjunction with the first person of the Trinity, introduced them to the third person of the Trinity.
Also God, Himself. Also comforter. Also a counselor. Also a teacher. Also a guide.
And it happened because Jesus arose, and ascended to heaven.
Then the Holy Spirit came.
Our last special blessing of the Resurrection is the gift of the Spirit.