Al-Kāfi - Volume 3 > Preferences for Relatives and Those of Them to Whom Zakat Cannot Be Paid
Hadith #2

2ـ أَحْمَدُ بْنُ مُحَمَّدٍ عَنْ عَلِيِّ بْنِ الْحَكَمِ عَنْ مُثَنًّى عَنْ أَبِي بَصِيرٍ قَالَ سَأَلَهُ رَجُلٌ وَأَنَا أَسْمَعُ قَالَ أُعْطِي قَرَابَتِي زَكَاةَ مَالِي وَهُمْ لاَ يَعْرِفُونَ قَالَ فَقَالَ لاَ تُعْطِ الزَّكَاةَ إِلاَّ مُسْلِماً وَأَعْطِهِمْ مِنْ غَيْرِ ذَلِكَ ثُمَّ قَالَ أَبُو عَبْدِ الله (عَلَيْهِ الْسَّلام) أَ تَرَوْنَ أَنَّمَا فِي الْمَالِ الزَّكَاةُ وَحْدَهَا مَا فَرَضَ الله فِي الْمَالِ مِنْ غَيْرِ الزَّكَاةِ أَكْثَرُ تُعْطِي مِنْهُ الْقَرَابَةَ وَالْمُعْتَرِضَ لَكَ مِمَّنْ يَسْأَلُكَ فَتُعْطِيهِ مَا لَمْ تَعْرِفْهُ بِالنَّصْبِ فَإِذَا عَرَفْتَهُ بِالنَّصْبِ فَلاَ تُعْطِهِ إِلاَّ أَنْ تَخَافَ لِسَانَهُ فَتَشْتَرِيَ دِينَكَ وَعِرْضَكَ مِنْهُ.

2. Ahmad ibn Muhammad from has narrated from Ali ibn al-Hakam from Muthanna’ from abu Basir who has said the following: “Once someone asked him (the Imam) ‘Alayhi al-Salam, when I was hearing, saying, ‘Can I pay Zakat to my relatives and they do not know (this belief)? He (the Imam) said, ‘Do not pay Zakat to anyone who is not a Muslim, but give them from other things.’ Abu ‘Abd Allah, ‘Alayhi al-Salam, then said, ‘Do you think that Allah has made just Zakat obligatory on one’s assets? In fact, other things that Allah has made obligatory on one’s assets are more than Zakat. You pay to relatives, to one who asks you and you pay as long as you do not know him to be hostile; but when you learn that he is hostile, then do not pay him anything unless you are afraid of his tongue, in which case you buy your religion and dignity from him.’”