A word is defined by how it is used, the word "soul" as used in jazz, is almost sacred. It's used to describe the sound of the very few who project it.
The sound of soul can be projected in song or instrumental music. When you hear it, the sound resonates within the depths of your being. No need to understand the language, people from around the world experience the same profound emotions when they lose the love of a lifetime, and they instinctively know when such an event is projected through song or instrumental music.
Ray Charles, "The Sun Died";
https://www.youtube.com/watch?v=OpR8UrMQvnU
The words don't tell the story half as much as the sound of Ray Charles voice.
"The Sun Died"; there is no life without the Sun. Yesterday, he was in paradise gazing into her beautiful eyes.
Bobby Timmons is the unspoken master of instrumental soul;
https://www.youtube.com/watch?v=cNjRQo-zpKA&list=RDEMwn1l3d6X9Dhg9J52Gz5zMg&start_radio=1
That piano and the music says it all; each note makes a profound statement about down and out, and unable to do anything about it, except "Moan".
https://www.youtube.com/watch?v=cNjRQo-zpKA&list=RDEMwn1l3d6X9Dhg9J52Gz5zMg&start_radio=1
This song projects someone who is too tired to walk, but for whatever reason he has to keep going.