The Chapter on the Virtues of Prayer
Man Lā Yaḥḍuruh al-Faqīh|Volume 1|Book 1|Chapter 31
وَقَالَ عَلَيْهِ اَلسَّلاَمُ: «إِنَّ اَلْعَبْدَ إِذَا صَلَّى اَلصَّلاَةَ فِي وَقْتِهَا وَ حَافَظَ عَلَيْهَا اِرْتَفَعَتْ بَيْضَاءَ نَقِيَّةً، تَقُولُ حَفِظْتَنِي حَفِظَكَ اَللَّهُ وَ إِذَا لَمْ يُصَلِّهَا لِوَقْتِهَا وَ لَمْ يُحَافِظْ عَلَيْهَا اِرْتَفَعَتْ سَوْدَاءَ مُظْلِمَةً تَقُولُ ضَيَّعْتَنِي ضَيَّعَكَ اَللَّهُ.
Imam عليه السلام said: "When a servant performs prayer at its prescribed time and maintains it, it ascends as a pure, white light, saying, 'You preserved me, may Allah سبحانه وتعالى preserve you.' But if he does not perform it at its prescribed time and does not maintain it, it ascends as a dark, black shadow, saying, 'You neglected me, may Allah سبحانه وتعالى neglect you.'"
- Ṣaḥīḥ al-Faqīh