'Forgiveness' in the Bible

John the Baptist appeared in the wilderness preaching a baptism of repentance for the forgiveness of sins [that is, requiring a change of one’s old way of thinking, turning away from sin and seeking God and His righteousness].

but whoever blasphemes against the Holy Spirit and His power [by attributing the miracles done by Me to Satan] never has forgiveness, but is guilty of an everlasting sin [a sin which is unforgivable in this present age as well as in the age to come]”—