Al-Kāfi - Volume 6 > The Saltwort and Cyperus
Hadith #2

بَعْضُ أَصْحَابِنَا عَنْ جَعْفَرِ بْنِ إِبْرَاهِيمَ الْحَضْرَمِيِّ عَنْ سَعْدِ بْنِ سَعْدٍ قَالَ قُلْتُ لِأَبِي الْحَسَنِ ( عليه السلام ) إِنَّا نَأْكُلُ الْأُشْنَانَ فَقَالَ كَانَ أَبُو الْحَسَنِ ( عليه السلام ) إِذَا تَوَضَّأَ ضَمَّ شَفَتَيْهِ وَ فِيهِ خِصَالٌ تُكْرَهُ إِنَّهُ يُورِثُ السِّلَّ وَ يَذْهَبُ بِمَاءِ الظَّهْرِ وَ يُوهِي الرُّكْبَتَيْنِفَقُلْتُ فَالطِّينُ فَقَالَ كُلُّ طِينٍ حَرَامٌ مِثْلُ الْمَيْتَةِ وَ الدَّمِ وَ لَحْمِ الْخِنْزِيرِ إِلَّا طِينَ قَبْرِ الْحُسَيْنِ ( عليه السلام ) فَإِنَّ فِيهِ شِفَاءً مِنْ كُلِّ دَاءٍ وَ لَكِنْ لَا يُكْثَرُ مِنْهُ وَ فِيهِ أَمَانٌ مِنْ كُلِّ خَوْفٍ .

2. Certain persons of our people have narrated from Ja‘far ibn Ibrahim al-Hadramiy from Sa‘d ibn Sa‘d who has said the following: “I once said to abu al-Hassan, ‘Alayhi al-Salam, ‘I eat saltwort.’ He (the Imam) said, ‘Abu al-Hassan, ‘Alayhi al-Salam, when washing his hands and mouth (with saltwort) would keep his lips closed. There is a quality in it, which is disliked. It can cause tuberculoses, it takes away the water of the back and weakens the knees.’ I then asked about clay. He (the Imam) said, ‘Eating clay is unlawful like dead bodies, blood and pork except the clay and soil of the grave of al-Husayn, ‘Alayhi al-Salam, in which there is cure for all illnesses, however, do not be excessive, and there is immunity in it against all kinds of fear.’”