(CNN) They gathered at the Emanuel African Methodist Episcopal Church to study the Bible -- a small group, 13 people. Many were familiar faces. One was a stranger.
But it was unfathomable that this stranger was a killer lying in wait, a man who would kill nine churchgoers and church leaders in cold blood.
Police say Dylann Roof went to the church in Charleston, South Carolina, two hours from his home, and shot dead the pastor, other ministers and people who had come Wednesday to learn more about the Word of God.
Here's what we know about the deceased:
The Rev. Clementa Pinckney died Wednesday doing the work he had always felt was right for him.
He was spreading the Word when he and eight others were gunned down in the massacre.
Pinckney, 41, answered the call to preach nearly 30 years ago, at the age of 13, according to a biography on the church website.
He was a high achiever all his life. He was first appointed a pastor when he was 18. He graduated from Allen University magna cum laude and was president of the student body at the Columbia, South Carolina, school.
Back then, Ebony magazine even featured him as one of its "Top College Students in America."
In 1996, at 23, he was elected to the South Carolina House of Representatives, the youngest black person ever to win such a seat.
Four years later, voters elevated him to the state Senate.
Pinckney became even more influential through his work as a legislator, pushing several causes -- like recently advocating for legislation to make police wear body cameras, believing it would protect lives, according to his cousin, state Sen. Kent Williams.
Washington Post columnist David Broder called him a "political spirit lifter for surprisingly not becoming cynical about politics."
U.S. Rep. Mark Sanford, a former governor of South Carolina, was among those who paid tribute Thursday.
"He was a remarkable human being," Sanford told CNN's "New Day." "He had a gravelly, deep voice -- a radio announcer's voice, if you will -- and he approached life with that same level of gravitas."
Williams called Pinckney "a man of character." "He was a God-fearing man. He was a family man."
Williams added, "He had a passion for helping the poor, for helping to improve the quality of life for all mankind. But especially those who are the least among us."
Pinckney left behind a wife, Jennifer, and two children, Eliana and Malana.
Like Pinckney, the Rev. Daniel Simmons Sr. was on the staff at Emanuel and regularly attended the Wednesday night Bible study sessions.
The 74-year-old survived the initial shooting at the church, but he died during surgery.
Earlier in his career, Simmons served at Greater Zion AME Church in Awendaw, just northeast of Charleston.
Cynthia Hurd loved God, her family, books and her community, her brother Malcolm Graham told CNN.
He described her as the matriarch of the family and the glue that kept them together.
She was baptized in the church and went there her whole life. Her late mother sang in the choir.
So it was no surprise she would attend a weeknight Bible study.
Hurd's loss is "incomprehensible" to the Charleston County Public Library, where she worked.
In a statement, the library said she was much more than an employee. Hurd "dedicated her life to serving and improving the lives of others."
All 16 branches of the library were closed Thursday in honor of Hurd, 54, who was manager of the St. Andrews Regional Library. That branch will be renamed in her honor.
"We ask for prayers for her family, her co-workers, her church and this entire community as we come together to face this tragic loss," the library statement said.
Hurd had worked for the library -- "helping residents, making sure they had every opportunity for an education and personal growth" -- for 31 years, the statement said.
Her husband, Steve, was working as a longshoreman in Saudi Arabia, and the family is trying to get him home.
Hurd also had four older brothers, including Graham, and a younger sister.
Sharonda Singleton was living what would appear to be a full and busy life.
She was a speech therapist and track coach at Goose Creek High School about 20 miles north of Charleston, having been a track and field athlete when she attended South Carolina State University in Orangeburg.
She was also a reverend at Emanuel AME Church, and she was a member of a sporting family.
She was married to Christopher Singleton, who played football at Tennessee State University. And her son, Chris, who was born in 1995, plays baseball for Charleston Southern University.
Before fighting off tears as he hugged his teammates, Chris Singleton described his mother as "a God-fearing woman (who) loved everybody with all her heart."
"Love is always stronger than hate," he told reporters. "So if we just loved the way my mom would, then the hate won't be anywhere close to what it is."
Myra Thompson, 59, also died in the shooting, said Bishop Alphonza Gadsden, who was notified by the victim's family. Gadsden had known Thompson for a decade.
"She was a person who loved the Lord. Her every objective was to please Him in all that she did. She was teaching Bible study when she was killed," she said
Tywanza Sanders' profile picture on Facebook is a selfie showing a young man with a winning smile and a sideways cap.
Not only did he smile a lot, he made his friends happy.
"If you met him, you knew you had a good friend on your side, regardless of anything," T.J. Grant told CNN. "He made you smile even when you didn't want to smile."
His friend was very loving, especially of his family, Grant said. Sanders spoke of his mother often and went to see her all the time.
The 26-year-old died trying to save his aunt, Susie Jackson, Grant and A.J. Harley said they were told.
"It's just like Tywanza," Hartley, one of his best friends, told CNN. "He's always been there for everybody, especially to protect a family member. ... So it was good to hear ... that he didn't die in vain."
Sanders was a quiet yet well-known student known for his warm and helpful spirit, according to a statement from Allen University, from which he graduated in 2014 from its Division of Business Administration. His friends have renamed a scholarship at their James Island high school in his honor because "that's what he was all about ... being educated, stimulating yourself, growing intellectually," Hartley said.
Sanders' engagement in his community, and his sense of self, were also evident in his social media posts -- including some from just hours before the shooting.
That includes a Facebook post, around 6 p.m. ET Wednesday, featured a video and the words, "Ever notice how the mainstream media treats black protesters & white rioters differently?"
That same day, he put up this quote from baseball groundbreaker Jackie Robinson: "A life is not important except in the impact it has on other lives."
This was a young man seemingly intent on going places. His cover photo on Facebook -- the banner photo that spreads behind the profile picture and tops the page -- featured only words in light letters set against a dark background.
They said simply: "Your dreams are calling you."
The Rev. DePayne Middleton-Doctor was a school administrator, a passionate Christian and the mother of four daughters, according to friends and colleagues.
The 49-year-old Middleton-Doctor started working in December as an admissions coordinator at the Charleston learning center of her alma mater, Southern Wesleyan University, a Christian college.
"Always a warm and enthusiastic leader, DePayne truly believed in the mission of SWU to help students achieve their potential by connecting faith with learning," university President Todd Voss said.
She received her Master's degree in management from the school in 1994 after doing her undergraduate work in biology and life sciences at Columbia College. She was an experienced grant writer and was a consultant for school districts before joining Southern Wesleyan, the school said.
The Rev. George McKain, the national public affairs director for AME Zion Church who was in a bible study in North Charleston at the time of the shooting, recalled how Middleton-Doctor as an enthusiastic singer who had "a heart for missions, Christian education, loving all people (and) respective all generations."
"She could just bring out the praises of God," McKain told CNN. "She a delight to know, a joy and a light in the midst of darkness."
Susie Jackson, 87, was a longtime member of the historic Charleston church, her grandson told CNN affiliate WEWS in Cleveland. Tim Jackson remembered his grandmother as a "very helpful person."
She was a choir member and also was on the usher board of the church, where she had been a member for many years.
Susie Jackson was a very loving, giving person with a great smile, her grandson told the station.
Even before her death, Ethel Lance's former co-workers missed her dearly.
The 70-year-old had retired in 2002, but she left her mark at the Gaillard Auditorium. She ruled the auditorium's backstage for 34 years, said Cam Patterson, Charleston's director of special facilities.
"Nobody dared try to move into her territory. That was her pride and joy," Patterson said.
Lance was a wonderful employee and person, Patterson said.