u/FickleYes

I can imagine the song very clearly - it played during a character's death in a show or movie I think.
The main part is a child, or a children's choir singing something that sounds like "though the sins are all gone."

From my memory it has a similar tune to Dirty Money - Coming Home ft. Skylar Grey.
https://www.youtube.com/watch?v=FOXfbTx_P7c

The choir/kid part is very high-pitched.