Kur’an 17:85 — sura Al-Isra, 85. ajet

وَيَسۡـَٔلُونَكَ عَنِ ٱلرُّوحِۖ قُلِ ٱلرُّوحُ مِنۡ أَمۡرِ رَبِّي وَمَآ أُوتِيتُم مِّنَ ٱلۡعِلۡمِ إِلَّا قَلِيلٗا

Pitaju te o duši. Reci: "Šta je duša – samo Gospodar moj zna, a vama je dato samo malo znanja."

And they ask you, [O Muhammad], about the soul. Say, "The soul is of the affair of my Lord. And mankind have not been given of knowledge except a little