Appears 3 times in the Quran.
17:107 قُلْ ءَامِنُوا۟ بِهِۦٓ أَوْ لَا تُؤْمِنُوٓا۟ إِنَّ ٱلَّذِينَ أُوتُوا۟ ٱلْعِلْمَ مِن قَبْلِهِۦٓ إِذَا يُتْلَىٰ عَلَيْهِمْ يَخِرُّونَ لِلْأَذْقَانِ سُجَّدًا
Say: Believe in it or believe not; surely those who are given the knowledge before it fall down on their faces, making obeisance when it is recited to them.
And they fall down on their faces weeping, and it adds to their humility.
Surely We have placed chains on their necks, and these reach up to their chins, so they have their heads raised aloft.