Aguilera, who includes the song in her shows, offered this tribute to the 73-year-old R&B legend for PEOPLE:
"It isn't every day that an artist can meet the person who inspired them and their career. Not only did I have the incredible opportunity of meeting my idol, the legendary Ms. Etta James, but to be asked by her family to perform at her memorial was so very touching and yet bitter sweet.
"Etta wasn't just any performer, she was a strong woman whose talent came from a place so deep it moved people in ways they never felt before. Losing her was, to me, like losing a part of my soul.
"I can only hope that she felt the love in the room as we all came together to pay tribute to her and celebrate her life as a person and as an artist. She will be deeply missed and I thank her family for allowing me such a great honor."
– Christina Aguilera