Arabic Sources
‘Encyclopedia de l'Islam', Leiden-Paris, 1983
“In ancient Arab poetry, nafs means the self or the person, while ruch meant ‘breath' and ‘wind'. In the Koran, nafs also means soul, and ruch means a special angel messenger and a particular divine quality. It is only in the post-quranic literature (that the terms nafs and Ruch) have the same meaning and serve to designate the human spirit, the angels and the djins”...
Ruch in the Koran
in the Koran, Ruch has 5 meanings:
1. Allah has blown from His Ruch into Adam, giving life to his body. (15,29-38, 72-32, 8) and into Mary for the conception of Isa (21, 91 and 66,12).
Ruch is here the same thing as ‘rih' and means ‘Breath of Life' (see also Gen 11,7).
2. ...therefore the Ruch is the special gift Allah bestows on those who are his prophets.
3. In 4,169, Isa is called ‘the ruch coming from Allah'.
4. (missing reference)
5. In 26,193, the faithful Ruch (al-ruch, al-amin), descends into the body of Mohammed to reveal the Koran to him.