وَنَفْسٍ وَمَا سَوَّاهَا
And by a soul and the fashioning of it. (91:7)
Nafsin is indefinite. It can point to the human soul as a class or heighten the significance of its fashioning; the wording alone does not identify a named individual. Sawwāhā evokes due proportion and shaping.
The movement from sky and earth to the soul shifts the listener from the cosmic scene to inner moral experience. This sequence provides a meaningful link among apparently diverse oath objects.