Hadith 1244
Mishkat al-Masabih
Prayer · Moderation in what is done - Section 1
Arabic
وَعَنْ أَنَسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: " لِيُصَلِّ أَحَدُكُمْ نَشَاطَهُ وَإِذَا فَتَرَ فَلْيَقْعُدْ)
English translation
Anas reported God’s Messenger as saying, “One should pray as long as he is lively, but when he slackens he should stop.” (Bukhari and Muslim.)