"The Messenger of Allah said: 'If the people knew what (reward) there is in the 'Isha' prayer and fajr prayer, they would come even if they had to crawl.'"  

قَالَ رَسُولُ اللَّهِ ﷺ لَوْ يَعْلَمُ النَّاسُ مَا فِي صَلاَةِ الْعِشَاءِ وَصَلاَةِ الْفَجْرِ لأَتَوْهُمَا وَلَوْ حَبْوًا  

"The Messenger of Allah said: 'The most burdensome prayers for the hypocrites are the 'Isha' prayer and the Fajr prayer. If only they knew what (reward) there is in them, they would come to them even if they had to crawl.'"  

قَالَ رَسُولُ اللَّهِ ﷺ إِنَّ أَثْقَلَ الصَّلاَةِ عَلَى الْمُنَافِقِينَ صَلاَةُ الْعِشَاءِ وَصَلاَةُ الْفَجْرِ وَلَوْ يَعْلَمُونَ مَا فِيهِمَا لأَتَوْهُمَا وَلَوْ حَبْوًا  

The Prophet used to say: "Whoever performs prayer in congregation at the mosque for forty nights, never missing the first Rak'ah of the 'Isha' prayer, Allah will thereby decree for him salvation from the Fire."  

عَنِ النَّبِيِّ ﷺ أَنَّهُ كَانَ يَقُولُ مَنْ صَلَّى فِي مَسْجِدٍ جَمَاعَةً أَرْبَعِينَ لَيْلَةً لاَ تَفُوتُهُ الرَّكْعَةُ الأُولَى مِنْ صَلاَةِ الْعِشَاءِ كَتَبَ اللَّهُ لَهُ بِهَا عِتْقًا مِنَ النَّارِ