عَنْ أَبِي يَسْرٍ الْأَنْصَارِيِّ كَعْبِ بْنِ عَمْرٍو رَضِيَ اللَّهُ عَنْهُ صَاحِبِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ قَالَ: ((مِنْكُمْ مَنْ يُصَلِّي الصَّلَاةَ كَامِلَةً وَمِنْكُمْ مَنْ يُصَلِّي النِّصْفَ وَالثُّلُثَ وَالرُّبُعَ حَتَّى بَلَغَ الْعُشْرَ))
It is narrated from the Companion of the Messenger, Sayyiduna Abu Yasar Ka'b bin Amr Ansari (may Allah be pleased with him), that the Messenger of Allah (peace and blessings be upon him) said: Among you, some people perform the complete prayer, some perform half of it, some a third, and some a quarter, ... until the Prophet (peace and blessings be upon him) reached a tenth part.