To blasphemy the Holy Spirit is to attribute to His work the power of Satan. Now, in these times the Holy Spirit testifies to Jesus Christ and convicts the world of sin, righteousness, and judgment.
John 15:26
"When the Helper comes, whom I will send to you from the Father, that is the Spirit of truth who proceeds from the Father, He will testify about Me,"
John 16:7-11
"But I tell you the truth, it is to your advantage that I go away; for if I do not go away, the Helper will not come to you; but if I go, I will send Him to you. "And He, when He comes, will convict the world concerning sin and righteousness and judgment; concerning sin, because they do not believe in Me; about righteousness, because I am going to the Father, where you can see me no longer; and about judgment, because the prince of this world now stands condemned."
This means that to blasphemy the Spirit of Jesus Christ is to attribute the testimony of Jesus Christ and the conviction of sin, righteousness, and judgment by the Holy Spirit to the devil. As many of those in other religions do to their destruction. However, if you believe in Jesus Christ, how can this be a problem?
I am a novice to the study of who has or has not the Holy Spirit. But Revmithell's point is poignant. By the end of Acts those with the Spirit are those that believe. Baptism or the laying on of hands by the apostles, as far as I know from my pastor not from my own study, was required in some cases, early in the ministry of the Gospel. That is not the case now. Although, obedience calls for all to be baptized who confess Jesus Christ. Those that confess Christ have responded to the Holy Spirit and are saved:
John 3:18
Whoever believes in Him is not condemned, but whoever does not believe has already been condemned, because he has not believed in the name of God's one and only Son.
John 3:36
Whoever believes in the Son has eternal life. Whoever rejects the Son will not see life. Instead, the wrath of God remains on him."