Authentic
graded by Al-Albani
Mishkat al-Masabih 868
Narrator:Anas ibn Mālik
عَنْ أَنَسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «أَقِيمُوا الرُّكُوعَ وَالسُّجُودَ فَوَاللَّهِ إِنِّي لأَرَاكُمْ من بعدِي»
Anas reported God’s Messenger as saying, “Perform the bowing and the prostration properly, for I swear by God that I can see you behind me." (Bukhari and Muslim.)
Cited in Mishkat al-Masabih (No. 868).