I have two comments and hope they are not deemed rude.

Firstly, why is this article not framed correctly as an infomercial? http://ramify.biz/2017/03/08/mc-saatchi-abel-forges-alliance-zeitz-museum-contemporary-art-africa/ 

Secondly, the closest to a 'healing soul' argument in the philosophy of art would be Aristotle and his notion that poetry evokes fear and pity which leads to a catharsis in the reader/viewer. Of course, here he had in mind the tragedies like 'Oedipus the King' and the works of Homer which had some pretty gruesome scenes such as Achilles' killing of Hector. This strongly discounts Mr Abel's healing soul position. I am not sure a single theorist from Plato to Danto would have ever claimed that art is, in Mr Abel's sense, a soul healer. This theory, I am sorry to say, seems to me to be PR agency's attempt to market art, to make contemporary​ art a little more anodyne for the Constantia/Santon dweller who finds van Gogh's struggles with mental illness 'so beautiful'.