"(But this spake he of the Spirit, which they that believe on him should receive: for the Holy Ghost was not yet given; because that Jesus was not yet glorified.)"
This does not mean that the Holy Spirit had not operated before Pentecost, but only that He had not been manifested in His fullness. Only after Jesus was glorified at His ascension were the assembled praying, waiting disciples to receive the Holy Spirit according to the promise (Acts 1:8, 9; 2:1-4).
The Holy Spirit had been manifested at the time of Creation (Genesis 1:2) and just before the Flood (Genesis 6:3). David prayed, "Take not thy holy spirit from me." Psalm 51:11. The Scriptures record also that"the Spirit of the
Lord departed from Saul." 1 Samuel 16:14. But only after tarrying at Pentecost did the disciples receive the promised blessing of the fullness of the Holy Spirit, at the time appointed by Christ.