The discussion also reports a philosophical account of subsistence. To be subsisting in itself is to be independent of a substratum as bearer; to subsist in another is to be present as a feature or quality of something else.
The relationship is described using the terms naʿt (attribute) and manʿūt (that which is characterized): one reality functions as a quality and the other as its bearer.
Similar language between theologians and philosophers does not make every conclusion identical. The meaning assigned to a technical term must be established before an argument is transferred from one system to another.