If one looks for a definition of the balm of Gilead aside from questionable unguents and speculative associations that have little or no biblical relevance as far as I can see, though they are comforting, the evidence is thin.We don't know who composed the gospel song, a black spiritual, but the root may be Genesis 31.
However, despite unmentioned anywhere else, all that I can find is Genesis 31. It is the story of Jacob and Laban. Jacob goes to the land of his mother's brother to find a wife. He falls for Rachel the younger but is given the elder Leah and for that must work for seven years for Laban. Then he is given Rachel for seven more years of work and a further six years piled on. Jacob has had enough and removes his wives and children and flocks and surreptitiously escapes to the hill country of Gilead across the Euphrates hotly pursued by Laban.
Things look bad but Jacob has obeyed God in this move, and moreover God has also appeared to Laban and cautioned him about no nonsense. They meet in the hill country of Gilead and know that they are kinsmen. Together they build a heap of stones they name Gileed. They build together a pillar they name Mizpah which means watch point. These symbols are a witness. Anger is comforted and soothed Laban kisses his daughters and grandchildren and leaves to his side of the pillar and the Gileed. Jacob goes on to his life with his wives and children and flocks.
This may be the balm of Gilead. This Easter Day It could be a balm for the troubles around the world.