I heard the Prophet (ﷺ) saying, "Our Lord (Allâh) will lay bare His Shin and then all the believers, men and women, will prostrate themselves before Him, but there will remain those who used to prostrate in the world for showing off and for gaining good reputation. Such one will try to prostrate (on the Day of Judgement) but his back bones will become a single vertebra bone (so he will not be able to prostrate)." [6:441-O.B]