A book by Hillary Clinton's spiritual adviser, the Rev. Bill Shillady, is being pulled from shelves less than a month after its release after the publisher found it contained extensive plagiarism

A book by Hillary Clinton‘s spiritual adviser, the Rev. Bill Shillady, is being pulled from shelves less than a month after its release after the publisher found it contained extensive plagiarism.

Clinton wrote the foreword for the book — Strong for a Moment Like This, a collection of devotionals that Shallidy had emailed the former Democratic nominee daily throughout her 2016 presidential campaign — and credited the United Methodist Church minister with helping her recover after her crushing loss to Donald Trump in November.

Get push notifications with news, features and more.

The Rev. Brian K. Milford, the president of the publishing company, Abingdon Press, that printed the book, said in a statement: “Following the discovery of unattributed passages in the November 9 devotional of Strong for A Moment Like This, Abingdon Press initiated an extensive review of the book and was alarmed to discover other content unattributed by the author. Abingdon Press has zero tolerance for plagiarism. Consequently, we have discontinued sales, will remove existing copies from all sales outlets, and will have them destroyed along with our existing inventory.”

Shillady added in a statement to PEOPLE: “I deeply regret the situation. I apologize to those whose work I mistakenly did not attribute. I apologize to those who must be disappointed, including Secretary Hillary Clinton, Abingdon Press, and all the writers and others who have helped me publish and promote this book. I ask for everyone’s forgiveness as we work to set things straight.”

WATCH: Hillary Clinton Compares Donald Trump to Richard Nixon in Wellesley College Commencement Speech

The book first became controversial after it was reported last month that Shillady had plagiarized a headline-making prayer he sent Clinton the day after she lost the election. Clinton had publicly praised the devotional, “Sunday Is Coming,” saying it helped her heal.

Shillady said in a statement to PEOPLE at the time that he was “stunned” to learn that the prayer was so similar to one written by the Rev. Matt Deuel of Mission Point Community Church in Warsaw, Indiana.

“My entire approach to this book project has been to credit all of the many ministers and sources who contributed to the devotionals that were written for Hillary over the course of the campaign,” Shillady said. “In preparing the devotional on the morning of November 9, 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.”

Shillady has also pulled out of a scheduled public conversation with Clinton about her faith at Riverside Church in New York City on Thursday night. The event will still take place, with the Rev. Ginger Gaines-Cirelli, the pastor of Clinton’s church in Washington, D.C., the Foundry, moderating the conversation.