Al-Kāfi

Hadith 1399
sincerityprayer-etiquette
4ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ وَمُحَمَّدُ بْنُ إِسْمَاعِيلَ عَنِ الْفَضْلِ بْنِ شَاذَانَ جَمِيعاً عَنْ حَمَّادِ بْنِ عِيسَى عَنْ حَرِيزٍ عَنِ الْفُضَيْلِ بْنِ يَسَارٍ عَنْ أَبِي جَعْفَرٍ وَأَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) أَنَّهُمَا قَالاَ إِنَّمَا لَكَ مِنْ صَلاَتِكَ مَا أَقْبَلْتَ عَلَيْهِ مِنْهَا فَإِنْ أَوْهَمَهَا كُلَّهَا أَوْ غَفَلَ عَنْ أَدَائِهَا لُفَّتْ فَضُرِبَ بِهَا وَجْهُ صَاحِبِهَا.
4. Ali ibn Ibrahim has narrated from his father and Muhammad ibn ’Isma‘il from al-Fadl ibn Shadhan all from Hammad ibn ‘Isa from Hariz from Fudayl ibn Yasar who has said the following: “Abu Ja‘far, and abu ‘Abd Allah, ‘Alayhim al-Salam, have said, ‘Of your Salah (prayer) only that much is for you which you have performed with love. If one instills delusion in Salah (prayer) or omits it altogether, then such Salah (prayer) is rolled up and is struck against the face of its owner.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī