Titled Strong for a Moment Like This: The Daily Devotions of Hillary Rodham Clinton, the book published by Abingdon Press includes 365 of over 600 devotions Rev Bill Shillady wrote to Clinton from April 2015 through December of last year during the 2016 presidential campaign.
The United Methodist minister holds the copyright on the book, which includes a forward by Clinton herself and 11 pages of end notes crediting some source material.
It does not however credit one source from a blog post by Rev Matthew Deuel, a pastor at Mission Point Community Church in Warsaw, Indiana.
According to CNN, Rev Shillady apologised, saying he was "stunned" by the similarities between his email to Clinton and Deuel's column.
On 9th November, the day after the election, Rev Shillady sent Clinton an email titled, "Sunday is Coming".
Rev Deuel contacted a CNN reporter last week saying some paragraphs in Rev Shillady's writings appeared to be "inspired" by a blog he wrote in March 2016.
Rev Deuel wrote in his post: "For the disciples and Christ followers in the first century, Good Friday represented the day that everything fell apart. All was lost. The momentum and hope of a man, claiming to be the Son of God, the Messiah who was supposed to change everything, had been executed."
Rev Shillady's email to Clinton, published in his book, said: "For the disciples and Christ's followers in the first century, Good Friday represented the day that everything fell apart. All was lost. The momentum and hope of a man claiming to be the Son of God, the Messiah who was supposed to change everything, had been executed."
In a text message to CNN, Rev Deuel said he and Rev Shillady had talked and that he had accepted Rev Shillady's apology.
While Rev Shillady initially claimed to the American network that the devotions he sent to Clinton often included material he found on the Internet or old sermons he delivered as a former pastor, he later took more responsibility for the plagiarism.
In a statement, Rev Shillady said: "In preparing the devotional on the morning of 9th November, I was determined to provide comfort with the familiar adage that 'It's Friday But Sunday is Coming'.
"I searched for passages that offered perspective of this theme. I am now stunned to realize the similarity between Matt Deuel's blog sermon and my own. Clearly, portions of my devotional that day incorporate his exact words. I apologise to Matt for not giving him the credit he deserves."
Deuel said he was "shocked" when he read the minister's email to Clinton online but amid turmoil in the United States and elsewhere, he was "not interested in publicly pursuing anything.
He went on to say: "The last thing the world needs right now is two pastors having a public dispute over a blog. The reality is, there's nothing new under the sun.
"If my blog then, in turn, inspired Rev Shillady and it was used to encourage Hillary Clinton, then praise God for that! Could it have been done differently? Probably."