Of the Spirit - Of the Holy Spirit, that should be sent down to attend their preaching and to convert sinners.
For the Holy Ghost was not yet given - Was not given in such full and large measures as should be after Jesus had ascended to heaven. Certain measures of the influences of the Spirit had been always given in the conversion and sanctification of the ancient saints and prophets; but that abundant and full effusion which the apostles were permitted afterward to behold had not yet been given. See Acts 2; Acts 10:44-45.
Jesus was not yet glorified - Jesus had not yet ascended to heaven - to the glory and honor that awaited him there. It was a part of the arrangement in the work of redemption that the influences of the Holy Spirit should descend chiefly after the death of Jesus, as that death was the procuring cause of this great blessing. Hence, he said John 16:7, “It is expedient for you that I go away; for if I go not away the Comforter will not come unto you; but if I depart I will send him unto you.” See also John 7:8-12; John 14:15-16, John 14:26. Compare Ephesians 4:8-11.