عَنْ أَنَسٍ قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يُفْطِرُ مِنَ الشَّهْرِ حَتَّى يُظَنَّ أَنْ لَا يَصُومَ مِنْهُ وَيَصُومُ حَتَّى يُظَنَّ أَنْ لَا يُفْطِرَ مِنْهُ شَيْئًا وَكَانَ لَا تَشَاءُ أَنْ تَرَاهُ مِنَ اللَّيْلِ مُصَلِّيًا إِلَّا رَأَيْتَهُ وَلَا نَائِمًا إِلَّا رَأَيْتَهُ. رَوَاهُ البُخَارِيّ

Abu Huraira reported God’s Messenger as saying, “The religion is ease, but if anyone overdoes it it gets the better of him; so keep to the right course, approximate to perfection, rejoice, and ask help in the morning, the evening, and some of the latter part of the night.” Bukhari transmitted it.