And I have some verses for you. What do these mean?
Genesis17:19 Then God said, “Yes, but your wife Sarah will bear you a son, and you will call him Isaac. I will establish my covenant with him as an everlasting covenant for his descendants after him. 20 And as for Ishmael, I have heard you: I will surely bless him; I will make him fruitful and will greatly increase his numbers. He will be the father of twelve rulers, and I will make him into a great nation. 21 But my covenant I will establish with Isaac...
Then this one...
Genesis 22:2 Then God said, “Take your son, your only son, whom you love—Isaac—and go to the region of Moriah. Sacrifice him there as a burnt offering
Not that I believe these things really happened. But it is what the Bible says. Abraham is a prophet, but there is nothing that would make him a manifestation. It clearly says that Isaac was taken to be sacrificed and the covenant will be through Isaac.
As far as your question goes, I don't think it is a Messianic prophecy, but a prophecy about the Holy Spirit descending on Pentecost.
John 16:12 “I have much more to say to you, more than you can now bear. 13 But when he, the Spirit of truth, comes, he will guide you into all the truth. He will not speak on his own; he will speak only what he hears, and he will tell you what is yet to come. 14 He will glorify me because it is from me that he will receive what he will make known to you. 15 All that belongs to the Father is mine. That is why I said the Spirit will receive from me what he will make known to you.”
Acts 1:1 In my former book, Theophilus, I wrote about all that Jesus began to do and to teach 2 until the day he was taken up to heaven, after giving instructions through the Holy Spirit to the apostles he had chosen. 3 After his suffering, he presented himself to them and gave many convincing proofs that he was alive. He appeared to them over a period of forty days and spoke about the kingdom of God. 4 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. 5 For John baptized with water, but in a few days you will be baptized with the Holy Spirit.”
Acts 2:1 When the day of Pentecost came, they were all together in one place. 2 Suddenly a sound like the blowing of a violent wind came from heaven and filled the whole house where they were sitting. 3 They saw what seemed to be tongues of fire that separated and came to rest on each of them. 4 All of them were filled with the Holy Spirit and began to speak in other tongues as the Spirit enabled them.
I understand that Baha'is would like everything their religion teaches to be true, and I know that for Baha'is, the answers given in the Baha'i writings satisfies them. But they don't quite fit with what the Bible and the NT says. So, do Baha'is believe in the Bible and the NT? No, they believe in the Baha'i interpretation of them. Which gives us four manifestations out of the Jewish religion, Adam, Noah, Abraham and Moses. Which gives us Ishmael instead of Isaac. Which gives us Baha'u'llah as the Spirit of Truth and not the Holy Spirit. And it makes Jesus physically dead and having never resurrected. Just a slight difference between Judaism and Christianity.