Messenger of Allah (S) said: "The most virtuous fasting after the month of Ramadan is that of Allah's month of Al-Muharram. And the most virtuous Salat after the obligatory is the night prayer."  

قَالَ رَسُولُ اللَّهِ ﷺ أَفْضَلُ الصِّيَامِ بَعْدَ شَهْرِ رَمَضَانَ شَهْرُ اللَّهِ الْمُحَرَّمُ وَأَفْضَلُ الصَّلاَةِ بَعْدَ الْفَرِيضَةِ صَلاَةُ اللَّيْلِ قَالَ وَفِي الْبَابِ عَنْ جَابِرٍ وَبِلاَلٍ وَأَبِي أُمَامَةَ