The Spirit manifested himself in the bodily form of a dove to anoint Jesus as his Anointed One for his ministry as an apostle with regard to the kingdom of God.
The holy Spirit was not available to others while Jesus was human.
On the Last Day, that great day of the feast, Jesus stood and cried out, saying, “If anyone thirsts, let him come to Me and drink. He who believes in Me, as the Scripture has said, out of his heart will flow rivers of living water.”
But this He spoke concerning the Spirit, whom those believing in Him would receive; for the Holy Spirit was not yet given, because Jesus was not yet glorified. (John 7:37-39)
Your postulation is untrue because the word
"given", (which I highlighted in
bold red italics), appears nowhere in any Greek text but has rather been inserted into the text by your favorite translators. You therefore do not understand what you are reading in that text because it speaks not of a Spirit
as entity but rather speaks of the Testimony of Yeshua, which is Spirit, (according to his own Testimony in John 6:62-63), and which Testimony is likewise the Spirit of Grace, (and the blood of our Covenant, Hebrews 10:29), for Testimony is SPIRIT, and the Testimony of Yeshua was "not yet" in the John passage because it was not yet complete until the Master says, at Golgotha, "IT IS FINISHED!"
John 7:39 YLT (Young's Literal Bible Translation)
39 and this he said of the Spirit, which those believing in him were about to receive; for not yet was the Holy Spirit, because Jesus was not yet glorified.
The Holy Spirit was
not yet because Yeshua was
not yet glorified. And Yeshua was "glorified", (meaning exalted or lifted up in this sense), when he was lifted up at Golgotha on the stake, even as he says: as Moshe lifted up the Seraph, on a staff or pole, in the desert wilderness. You are therefore confusing Testimony-Spirit with the Name found in Genesis 1:2 and Matthew 3:16, which Name is Ruach Elohim, (anarthrous, no article, and therefore much more likely a personal pronoun, a name, (denoting entity)).