The Prophet ﷺ used to say, "Nobody should be flogged more than ten stripes except if he is guilty of a crime, the legal punishment of which is assigned by Allah."  

كَانَ النَّبِيُّ ﷺ يَقُولُ لاَ يُجْلَدُ فَوْقَ عَشْرِ جَلَدَاتٍ إِلاَّ فِي حَدٍّ مِنْ حُدُودِ اللَّهِ