Anas bin Malik narrated that the Messenger of Allah ﷺ said:

"The parable of the ill when he is cured and becomes healthy is that of hail that falls from the heavens in its purity and its color."

حَدَّثَنَا عَلِيُّ بْنُ حُجْرٍ، قَالَ أَخْبَرَنَا الْوَلِيدُ بْنُ مُحَمَّدٍ الْمُوَقَّرِيُّ، عَنِ الزُّهْرِيِّ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ قَالَ رَسُولُ اللَّهِ ﷺ " إِنَّمَا مَثَلُ الْمَرِيضِ إِذَا بَرَأَ وَصَحَّ كَالْبَرْدَةِ تَقَعُ مِنَ السَّمَاءِ فِي صَفَائِهَا وَلَوْنِهَا " .