'Christmas Sermon' by author C.S. Lewis warned of a world that no longer knew right from wrong

The Christian faith of early 20th-century Irish author C.S. Lewis is enjoying a rebirth right now as American culture, and the wider Western world, appear to have lost a sense of right and wrong.

Credit the recent rediscovery of the author's writings on religion, culture and morality, including "A Christmas Sermon for Pagans," published in December 1946 in Strand magazine.

The letter compared pagan, or what he called pre-Christian beliefs, to those that emerged during and after the global crises and warfare of the early 20th century. He called it "post-Christian" philosophy. 

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The sermon was written for an audience in the United Kingdom. 

But it addresses, with almost startling prescience, many of the same culture-war issues simmering for years in the United States and exploding across the nation after the Oct. 7 Hamas terror attacks on Israel. 

Irish-born academic Clive Staples Lewis (1898-1963), a fellow and tutor of Magdalen College, Oxford, 1950. (John Chillingworth/Getty Images)

"There is no objective right or wrong" among post-Christians, Lewis wrote in the "Christmas Sermon." 

"Each race or class can invent its own code or ‘ideology’ just as it pleases."

He added, "Now if the post-Christian view is the correct one, then we have indeed waked from a nightmare."

"There is no right or wrong. Each race or class can invent its own code or ‘ideology’ just as it pleases." — C.S. Lewis

The "Christmas Sermon" has trended on social media. Discussions of Lewis’ concepts of moral certainty have appeared in recent scholarly articles and in discussions among Christians and Americans of other faiths.

The author's faith received nationwide exposure this month through "Advent with C.S. Lewis," a four-week-long prayer series introduced by Hallow app that included a collaboration and ads featuring actor Liam Neeson. 

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 "Lewis had a very profound impact on me," Hallow CEO Alex Jones told Fox News Digital, specifically citing the author's "The Screwtape Letters."

"He helped me change my own life."

Actor Liam Neeson pictured on Feb. 15, 2023. "Advent with C.S. Lewis" is a four-week-long prayer series introduced by Hallow app that includes a collaboration and ads featuring Neeson.  (Nathan Congleton/NBC via Getty Images)

Lewis is still well known today for his beloved fantasy novels, which were introduced to a new generation of fans in the 21st century with the success of "The Chronicles of Narnia" film series.

Neeson voices Aslan, a character in the "Chronicles" film adaptations. 

Lewis' Christian faith was well known in its time.

"Writing religion for skeptics has made C.S. Lewis a bestseller," Strand wrote in its introduction to the December 1946 article. 

Actors Liam Neeson and Jonathan Roumie from Hallow's "Advent with C.S. Lewis" campaign this December. (Courtesy Hallow)

"His books on Christianity — chief among them ‘The Screwtape Letters’ — sell better, and read more easily, than most crime stories."

The popularity of Lewis' religious writing faded over the decades. 

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Its disappearance was hastened by the general secularization of society and by a politically motivated effort to remove the foundational values of Christianity from American history and western culture.

Lewis examined his belief system, and that of the changing world, not just as an expression of faith but with the academic curiosity of a scholar. 

President Ronald Reagan biographer Craig Shirley called Lewis’ perspective the "intellectualism of Christianity." 

Ronald Wilson Reagan, 40th president of the United States, was deeply influenced by C.S. Lewis' faith, said biographer Craig Shirley. (Photo12/Universal Images Group via Getty Images)

Lewis’ writings had a profound influence on President Reagan, Shirley told Fox News Digital. 

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The president, not coincidentally, built his political foundation on personal beliefs, like Lewis, that the world was divided between right and wrong, good and evil. 

This outlook ultimately helped topple the Soviet Union and win the Cold War for western democracies, Shirley and other scholars have noted.

Lewis' warnings about a world that rejected Christian faith and foundational values in favor of a shifting morality appeared to become an unmistakable reality this autumn following the Oct. 7 terror attacks on Israel. 

Pro-Palestinian protest at Harvard University, Oct. 2023, left, and author C.S. Lewis, who warned of a culture that could no longer tell right from wrong. (Joseph Prezioso/AFP via Getty Images | John Chillingworth/Getty Images)

Some major institutions, including those of higher learning, have appeared unable to condemn terror attacks on Israeli civilians or threats of genocide against Jews on campuses — even comprehend why such things are wrong or dangerous.

"What he said has a lot of resonance … today, when people are wondering where the light is among all of this darkness." — Alex Jones

"Lewis spoke a lot about the fallen times of the world," said Jones of Hallow.

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"What he said has a lot of resonance with people with what’s going on in the world today, when people are wondering where the light is among all of this darkness."

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