Hillary Clinton's pastoral adviser, the Rev. Bill Shillady, has apologized to another Christian leader for plagiarizing the prayer message he sent the former Democratic presidential candidate a day after her election loss in November, according to multiple reports.

In a devotion for Clinton, Shillady had compared her November loss to Good Friday, the day Jesus was crucified. Shillady said Sunday, the day of Jesus' resurrection, was on the horizon.

"It is Friday, but Sunday is coming ... This is not the devotional you wish to receive this day. While Good Friday may be the starkest representation of a Friday that we have, life is filled with a lot of Fridays," wrote Shillady in an email to Clinton. "Friday is the day that it all falls apart and all hope is lost. We all have Fridays. But, as the saying goes, 'Sunday's coming!' "

Shillady, executive director of the United Methodist City Society, published a book of his devotions for Clinton and on Tuesday said he was "stunned" to find out about similarities between his and another pastor's metaphor, according to the Associated Press.

The post-election comparison of Clinton to Jesus was cited as the overarching theme in the book, just like a blog post by the Rev. Matt Deuel of Mission Point Community Church in Warsaw, Ind.

Despite being surprised, Shillady said he apologized to Deuel and gave him full credit for the comparison. His publisher, Abingdon Press, has maintained the incident was unintentional.

Shillady has maintained a pastoral relationship with the Clinton family for years.

Shillady co-officiated Chelsea Clinton's wedding to Marc Mesvinsky in July 2010 and led the memorial service for Hillary Clinton's mother, Dorothy Rodham.

Clinton and Shillady are scheduled to appear together at a New York event on Sept. 7.