A fad recirculating the internet calls for participants to record themselves on video renouncing the Holy Spirit.

The campaign, called the "Blasphemy Challenge," was created in 2006, but has a renewed popularity following the success of the ALS "Ice Bucket Challenge."

The "Blasphemy Challenge" was created by the atheist activist group, the Rational Response Squad. The group created the challenge as part of their "War on Christmas" campaign, and gave away free copies of the documentary "The God Who Wasn't There" to the first 1,001 people that completed the challenge.

The challenge, which was promoted on popular teen websites, involves the participant saying the words "I deny the Holy Spirit," on video. The Rational Response Squad cited Mark 3 as evidence that the assertion is an unforgivable sin, effectively damning a person's soul: "Truly I tell you, people can be forgiven all their sins and every slander they utter, but whoever blasphemes against the Holy Spirit will never be forgiven; they are guilty of an eternal sin" (Mark 3:28-29, New International Version).

Southern Evangelical Seminary Jewish Studies programme director, Dr Barry Leventhal, provided the context behind the controversial scriptures.

"Jesus had presented Himself as Messiah to the Jewish leaders. With irrefutable evidence, He had done everything necessary to validate who He was," Leventhal explained.

"For them to stubbornly maintain that posture of unbelief and then to attribute Christ's work to the devil—this rejection of God's overtures was the inexcusable, unpardonable, 'blasphemy of the Holy Spirit.'"

Therefore, according to Dr Leventhal, the statements made in the Blasphemy Challenge videos are not unforgivable.

"There is a difference between an unpardonable sin, and the unpardonable sin," he said. "The sin which ultimately places a person beyond God's forgiveness is to live and die in the act of unbelief. That is, to reject Christ."