Hadith 10016M

وقَال : " إِنَّ أَثْقَلَ الصَّلَاةِ عَلَى الْمُنَافِقِينَ ، صَلَاةُ الْعِشَاءِ وَالْفَجْرِ ، وَلَوْ يَعْلَمُونَ مَا فِيهِمَا لَأَتَوْهُمَا وَلَوْ حَبْوًا " .
And the two prayers that are heaviest upon the hypocrites are the ‘Isha prayer and the Fajr prayer. If they knew the reward for these prayers, they would certainly attend them, even if they had to crawl on their knees.
Hadith Reference مسند احمد / مسند المكثرين من الصحابة / 10016M
Hadith Grading حکم دارالسلام: إسناده صحيح، خ: 657، م: 651