President Obama’s singing of “Amazing Grace” during the eulogy for Rev. Clementa Pinckney, who was killed last month in a shooting at a Charleston church, has been widely acknowledged as one of the most powerful moments of his presidency. 
 
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 But when he first raised the idea with first lady Michelle Obama and senior adviser Valerie Jarrett, it was met with skepticism. 
 
 “Why on earth would that fit in?” the first lady said in reaction to the idea, according to Jarrett, who was with the Obamas as they departed the White House aboard Marine One on their way to the funeral in South Carolina. 
 
 Jarrett, who had once before tried unsuccessfully to dissuade the president from singing a line of Al Green's "Let's Stay Together," had a more subdued reaction. "Hmmm," Jarrett reacted. 
 
 The president went on to explain his thinking to Jarrett and the first lady, who had yet to read the president’s prepared eulogy, during the helicopter ride. 
 
 “I think if I sing, the church will sing with me,” Obama said, according to Jarrett, who recalled the story during a question answer session at the Aspen Institute’s Ideas Festival. 
 
 But even then, President Obama hadn’t made his mind up whether he would in fact sing. 
 
 “I don’t know whether I’m going to do it, but I just wanted to warn you two that I might sing,” Jarett recalled him saying. “We’ll see how it feels at the time.” 
 
 But as soon as the president took to podium to begin the eulogy, Jarrett said, it was clear the mood was right. 
 
 “From the first time he started to speak, the church was clearly with him,” Jarrett said. “He knew they were with him.” 
 
 Before the president began to sing, Jarrett observed that the president paused for a moment. And she later asked him, “Were you thinking about whether or not you were going to sing?” 
 
 “Oh no, I knew I was going to sing, I was just trying to figure out what key to sing in,” the president said in response to Jarrett. ||||| Photo 
 
 President Obama’s decision to sing “Amazing Grace” at the end of his eulogy for the Rev. Clementa Pinckney, a black pastor who was killed with eight others during Bible study in a Charleston, S.C., church last month, became one of the more memorable moments of his second term. But the idea raised at least some eyebrows when he first broached it with his closest confidants. 
 
 Mr. Obama was on the Marine One helicopter leaving the White House en route to Andrews Air Force Base for his flight to South Carolina when he mentioned the thought to Michelle Obama and Valerie Jarrett, their close friend and a White House senior adviser. 
 
 “When I get to the second part of referring to ‘Amazing Grace,’ I think I might sing,” he told them, by Ms. Jarrett’s account. 
 
 “Hmm,” Ms. Jarrett recalled responding. 
 
 Mrs. Obama was a little more pointed. “Why on earth would that fit in?” she asked. 
 
 He tried to explain. “I don’t know whether I’m going to do it,” he said, according to Ms. Jarrett, “but I just wanted to warn you two that I might sing.” He added, “We’ll see how it feels at the time.” 
 
 Ms. Jarrett told the story at the Aspen Ideas Festival last week in a session with Walter Isaacson, the Aspen Institute president. She noted that she had a little history with Mr. Obama’s singing career, recalling the 2012 fund-raiser at Harlem’s Apollo Theater when he crooned a little Al Green. 
 
 “I will confess to you that I was the voice back stage when he was being egged on by the electrical engineers who were doing the sound work for the show, ‘Go on, Mr. President, sing, sing,’” Ms. Jarrett said, referring to the 2012 event at the Apollo. “And I said, ‘Don’t sing! Don’t sing! Please, whatever you do, don’t sing.’ And of course, he sang. And it went over very well.” 
 
 So this time, she said, she knew better than to object and, in fact, in an email on Monday she said she and the first lady “both encouraged him to do whatever the spirit moved him to do.” 
 
 Many who watched him that day noted that he paused a long time before beginning to sing. 
 
 “So later I said to him, ‘Were you thinking about whether or not to sing?’” Ms. Jarrett recalled at Aspen. “He said, ‘Oh no, I knew I was going to sing. I was just trying to figure out which key to sing it.’”
– President Obama's rendition of "Amazing Grace" at the end of his eulogy for the Rev. Clementa Pinckney has been viewed more than 2 million times on YouTube. Had he listened to the gut reaction of those around him, it might not have happened at all. The New York Times and ABC News have the background on his decision to break out in song: Obama first shared his plan—to sing once he got "to the second part of referring to 'Amazing Grace'"—with Michelle Obama and senior adviser Valerie Jarrett while en route to Andrews Air Force Base to board his flight to South Carolina. "I think if I sing, the church will sing with me," he said, per Jarrett, who told the story during a Q&A at the Aspen Ideas Festival last week. How Jarrett says she responded: "Hmm." How Michelle put it: "Why on earth would that fit in?" Jarrett says he told them he wasn't convinced he'd go that route, but wanted to offer a warning. "We'll see how it feels at the time," she says he said. She says she and Michelle were ultimately encouraging, and as for the long pause before he began, she says that was a moment of debate ... but not about whether to go ahead. "I knew I was going to sing," he told her. "I was just trying to figure out which key to sing it."