(Imām Bukhārī narrates): Khālid ibn Makhlad narrated to us, he said: Sulaimān ibn Bilāl narrated to us, he said: Sharīk ibn 'Abdullāh narrated to us, he said: I heard Anas ibn Mālik, may Allāh be pleased with him, saying that:
I have never prayed behind any imām a lighter and more complete prayer than behind the Prophet ﷺ, and if he heard the sound of a child crying, he would shorten the prayer, out of fear that its mother would fall into distress.
حَدَّثَنَا خَالِدُ بْنُ مَخْلَدٍ، قَالَ: حَدَّثَنَا سُلَيْمَانُ بْنُ بِلاَلٍ، قَالَ: حَدَّثَنَا شَرِيكُ بْنُ عَبْدِ اللَّهِ، قَالَ: سَمِعْتُ أَنَسَ بْنَ مَالِكٍ، يَقُولُ: «مَا صَلَّيْتُ وَرَاءَ إِمَامٍ قَطُّ أَخَفَّ صَلاَةً، وَلاَ أَتَمَّ مِنَ النَّبِيِّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ وَإِنْ كَانَ لَيَسْمَعُ بُكَاءَ الصَّبِيِّ، فَيُخَفِّفُ مَخَافَةَ أَنْ تُفْتَنَ أُمُّهُ»
Reference: Sahih Al Bukhari 708