My Friend ﷺ instructed me in three (acts), and I would never abandon them as long as I live. (And these three things are): Three fasts during every month, the forenoon prayer, and this that I should not sleep till I have observed the Witr prayer. (Using translation from Muslim 722)   

أَوْصَانِي حَبِيبِي ﷺ بِثَلَاثٍ لَنْ أَدَعَهُنَّ مَا عِشْتُ بِصِيَامِ ثَلَاثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ وَصَلَاةِ الضُّحَى وَبِأَنْ لَا أَنَامَ حَتَّى أُوتِرَ