As-Suhayili mentioned the dispute among the scholars over whether the Ruh is
the same as the Nafs, or something different. He stated that it is light and
soft, like air, flowing through the body like water through the veins of a tree.
He states that the Ruh which the angel breathes into the fetus is the Nafs,
provided that it joins the body and acquires certain qualities because of it,
whether good or bad. So then it is either a soul in (complete) rest and
satisfaction (89:27) or inclined to evil (12:53), just as water is the life of
the tree, then by mixing with it, it produces something else, so that if it
mixes with grapes and the grapes are then squeezed, it becomes juice or wine.
Then it is no longer called water, except in a metaphorical sense. Thus we
should understand the connection between Nafs and Ruh; the Ruh is not called
Nafs except when it joins the body and is affected by it. So in conclusion we
may say: the Ruh is the origin and essence, and the Nafs consists of the Ruh and
its connection to the body. So they are the same in one sense but not in
another. This is a good explanation, and Allah knows best. I say: people speak
about the essence of the Ruh and its rulings, and many books have been written
on this topic. One of the best of those who spoke of this was Al-Hafiz Ibn
Mandah in a book which we have heard about the Ruh.
[وَلَئِن شِئْنَا
لَنَذْهَبَنَّ بِالَّذِى أَوْحَيْنَا إِلَيْكَ ثُمَّ لاَ تَجِدُ لَكَ بِهِ
عَلَيْنَا وَكِيلاً ]
[إِلاَّ رَحْمَةً
مِّن رَّبِّكَ إِنَّ فَضْلَهُ كَانَ عَلَيْكَ كَبِيرًا - قُل لَّئِنِ اجْتَمَعَتِ
الإِنسُ وَالْجِنُّ عَلَى أَن يَأْتُواْ بِمِثْلِ هَـذَا الْقُرْءَانِ لاَ
يَأْتُونَ بِمِثْلِهِ وَلَوْ كَانَ بَعْضُهُمْ لِبَعْضٍ ظَهِيرًا - وَلَقَدْ
صَرَّفْنَا لِلنَّاسِ فِى هَـذَا الْقُرْءَانِ مِن كُلِّ مَثَلٍ فَأَبَى أَكْثَرُ
النَّاسِ إِلاَّ كُفُورًا ]
(86. And if We willed, We could surely take away that which We have revealed
to you. Then you would find no protector for you against Us in that respect.)
(87. Except as a mercy from your Lord. Verily, His grace unto you is ever
great.) (88. Say: "If mankind and the Jinn were together to produce the like of
this Qur'an, they could not produce the like thereof, even if they helped one
another.'') (89. And indeed We have fully explained to mankind, in this Qur'an,
every kind of similitude, but most of mankind refuse (the truth and accept
nothing) but disbelief.)