Yo-Yo Ma played Bach’s Cello Suite No. 5 in C Minor at Thursday’s interfaith prayer and healing service in Boston, where the President and First Lady were in attendance after the tragedy of this week’s Boston Marathon.

In an interview with NPR earlier in the day, Yo-Yo Ma explained why he chose the piece: to paraphrase, the rise and fall of the notes signify the human struggle to overcome in the face of suffering (which is often one of getting up only to fall again)- and, the hard-won and eventual triumph of the human spirit.

In the same service, and in a similar vein, President Obama promised Bostonians that they would run again.

Maybe the greatest challenge to being human is, metaphorically speaking, learning to walk and then run again after having been crippled. This musical interlude goes out not just to all those impacted by this week’s events, but to all those everywhere who have ever been crippled by something and have struggled to walk again, albeit with a limp and after many falls and skinned knees. Yours is the victory in Christ Jesus: