Al-Kāfi
Hadith 1219عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ أَبِي عَبْدِ اللَّهِ عَنْ بَعْضِ أَصْحَابِهِ بَلَغَ بِهِ زُرَارَةَ قَالَ قُلْتُ لِأَبِي عَبْدِ اللَّهِ ( عليه السلام ) جُعِلْتُ فِدَاكَ الشَّحْمَةُ الَّتِي تُخْرِجُ مِثْلَهَا مِنَ الدَّاءِ أَيُّ شَحْمَةٍ هِيَ قَالَ هِيَ شَحْمَةُ الْبَقَرِ وَ مَا سَأَلَنِي يَا زُرَارَةُ عَنْهَا أَحَدٌ قَبْلَكَ .
6. A number of our people have narrated from Ahmad ibn ‘Abd Allah from certain persons of his people (and) brought by Zurarah who has said the following: “I once said to abu ‘Abd Allah (a.s.), ‘I pray to Allah to keep my soul in service for your cause, ‘Al-Shahmah (the fat) that expels the same amount of illness, which shahmah is it?’ He (the Imam) said, ‘It is shahmah of al-Baqar (cow) and no one before you has asked me about it.’”