Jason Duggar sang a song about forgiveness at church just two days before his older sister Jill Duggar is set to release her new memoir, Counting the Cost.

“I forgive you, but forgetting is the hardest thing to do,” Jason, 23, sang while standing in front of an audience at church, according to a video shared by blog Without A Crystal Ball on Sunday, September 10. “So my mind can’t comprehend how God could be that kind of friend.”

The former Counting On star went to sing about how God “forgives and forgets” and “canceled my debt.”

In Counting the Cost, which comes out on Tuesday, September 12, Jill, 32, opens up about what led to her fallout with Jim Bob Duggar and ​mom Michelle Duggar.

A source familiar with the book exclusively told In Touch that Jill “understands” Michelle, 56, better now as an adult than she did when she was a child. However, their relationship is no longer what it used to be. The insider explained that Jill “misses” how easy it used to be for her to communicate with Michelle before their estrangement.

Meanwhile, the source said Jill “never doubted” that her father loves his kids.

The book will also share insight into a conversation Jill had with Jim Bob, 58, about her decision to start wearing pants. While the Duggar parents raised their daughters to dress modestly and only wear skirts that went past their knees, a source tells In Touch that Jill decided to incorporate less strict styles into her own wardrobe after ​seeing women at church wear pants.

Jill wore leggings for the first time during a park day, though unexpectedly ran into some of her siblings. They then informed Jim Bob that she was wearing pants.

Days later, the Duggar patriarch confronted Jill about her choice to wear leggings, according to the insider. While Jim Bob acknowledged that Jill’s sister Jinger Duggar had already started wearing pants, he explained that Jinger, 29, called him and Michelle with arguments from the Bible to support her decision to change her wardrobe.

Jason Duggar Sings About ​'Forgiveness' at Church Days Before Sister Jill’s Book Release
D Dipasupil/Getty Images for Extra

Jim Bob then gave Jill a book that explained the importance of dressing modestly. While the conversation only included Jill and Jim Bob, the insider noted that she was “embarrassed” and “humiliated” by the interaction.

Counting the Cost is not the first time Jill has opened up about her complex relationships with her family. She previously revealed that Jim Bob “[controls] a lot of things in the family” in the June Prime Video docuseries Shiny Happy People: Duggar Family Secrets.

“Family relationships were already kinda rocky … Everything within the family dynamic has shifted, and not for the better,” the former TLC personality, who appeared in the docuseries with her husband, Derick Dillard, said. “We’re very much on the outside with the family.”