The shooting prompted Obama to reiterate his position on combatting gun violence in America.
"I've had to make statements like this too many times," Obama said. "We don't have all of the facts, but we do know that once again innocent people were killed in part because someone who wanted to inflict harm had no trouble getting their hands on a gun."
(RELATED: The Justice Department Has Opened a Hate-Crime Investigation Into Charleston Shooting)
The president continued, suggesting that the country has to act to prevent gun violence. "Now is the time for mourning and for healing, but let's be clear at some point, we as a country, we have to reckon with the fact that this mass violence does not happen in other advanced countries," Obama said. "It doesn't happen in other places with this kind of frequency. It is in our power to do something about it."
Obama: "This is not the first time that black churches have been attacked."
Vice President Joe Biden echoed these words in a joint statement with his wife released Thursday afternoon. "As a nation we must confront the ravages of gun violence and the stain of hatred that continues to be visited on our streets, in our schools, in our houses of worship, and in our communities," the Bidens said.
Obama said he and the first lady knew the pastor killed in Wednesday night's shooting. "To say that our thoughts and prayers are with them and their families and their community doesn't say enough to convey the heartache and the sadness and the anger that we feel," he said.
Charleston Mayor Joseph Riley said in a press statement that both President Obama and Vice President Biden have personally called him, offering condolences and assurances of federal support.
"We all woke up today, and the heart and soul of South Carolina was broken," said South Carolina Gov. Nikki Haley, fighting through tears. "We have some grieving and pain that we have to go through."
Obama often cites his own life and experience in trying to narrate horrific events and express empathy for victims. After the school shooting in Newtown, Connecticut, he referenced his feelings as a father whose daughters were not much different than those who were killed. In the wake of the death of Trayvon Martin and its resulting trial, Obama spoke of his experience being an African-American man in America.
The shooting in Charleston hits on both of these identities.
"The fact that this took place in a black church obviously also raises questions about a dark part of our history. This is not the first time that black churches have been attacked."
He quoted the words Dr. Martin Luther King said in the wake of the 1963 bombing of a black church in Birmingham, Alabama.
"'They [the ones who died] say to each of us,' Dr. King said, 'black and white alike, that we must substitute courage for caution. They say to us that we must be concerned not merely with who murdered them but about the system, and the way of life, the philosophy, which produced the murderers,'" Obama said, quoting King. "'Their death says to us that we must work passionately and unrelentingly for the realization of the American dream.'"