Matthew 12:31 - 32

31 “Therefore I say to you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven men.

32 Anyone who speaks a word against the Son of Man, it will be forgiven him; but whoever speaks against the Holy Spirit, it will not be forgiven him, either in this age or in the age to come.

Every kind of sin is able to be forgiven. All blasphemy is able to be forgiven except blasphemy directed at the Holy Spirit.

Blasphemy is defined as talk which is slanderous, denies what is accomplished, or is harmful to one's reputation.

If someone lies about the Holy Spirit, if someone denies the accomplishments of the Holy Spirit, or if someone speaks badly about the Holy Spirit to ruin the reputation of the Holy Spirit. It is directly ruled by Jesus the person will not be forgiven.

A person can tell anything about Jesus, about His motives for what He does, about the source of His powers, the Pharisees who claimed He was working with Satan and not against him, can be forgiven. One can concoct any bad story about Jesus as can be imagined and still be forgiven.

But speaking evil of the Holy Spirit would not be forgiven during the law of Moses times and it will not be forgiven during the new kingdom either. It does not matter what dispensation one lived or lives under, it is a sin of which forgiveness is not possible.

For one to be eligible for salvation all of one's sins must be forgiven before the last breath is taken here on earth. Blaspheming the Holy Spirit will never be forgiven and thus salvation will not be granted to the individual who is guilty of such.