SIN AGAINST HOLY SPIRIT
A sin that is often referred to as the "unpardonable sin" because, in the words of Jesus, "He who blasphemes [speaks evil] against the Holy Spirit never has forgiveness, but is subject to eternal condemnation" <Mark 3:29>.
The context of Jesus' words about the sin against the Holy Spirit provides a clue to its nature. When a demon-possessed man came to Jesus, He was healed. The multitudes were amazed. But the scribes and Pharisees said He was healing through Satan's power <Matt. 12:24>. Jesus had cast out the demons by the power of the Holy Spirit; His enemies claimed He cast them out by the power of the devil.
Such slander of the Holy Spirit, Jesus implied, reveals a spiritual blindness, a warping and perversion of the moral nature, that puts one beyond hope of repentance, faith, and forgiveness. Those who call the Holy Spirit Satan reveal a spiritual cancer so advanced that they are beyond any hope of healing and forgiveness
