Al-Kāfi

Hadith 1974
congregational-prayermosque
3ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنْ إِسْمَاعِيلَ بْنِ مَرَّارٍ عَنْ يُونُسَ عَنْ عَلِيِّ بْنِ يَقْطِينٍ قَالَ سَأَلْتُ أَبَا إِبْرَاهِيمَ (عَلَيْهِ السَّلاَم) عَنِ التَّقْصِيرِ بِمَكَّةَ فَقَالَ أَتِمَّ وَلَيْسَ بِوَاجِبٍ إِلاَّ أَنِّي أُحِبُّ لَكَ مَا أُحِبُّ لِنَفْسِي.
3. Ali ibn Ibrahim has narrated from his father from ‘Isma‘il ibn Marrar from Yunus from Ali ibn Yaqtin who has said the following: “I once asked abu Ibrahim (a.s.), about performing Salat (prayer) in reduced form in Makkah. He (the Imam) said, ‘You should perform in complete form; but it is not obligatory, except that I like for you what I like for myself.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī