Al-Kāfi
Hadith 75318- مُحَمَّدُ بْنُ يَحْيَى عَنْ مُحَمَّدِ بْنِ أَحْمَدَ عَنْ مُحَمَّدِ بْنِ عَبْدِ الْحَمِيدِ عَنْ أَبِي جَمِيلَةَ قَالَ دَخَلْتُ عَلَى أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) فَقَالَ لِي يَا شَابُّ أَيَّ شَيْءٍ تُعَالِجُ فَقُلْتُ الرَّقِيقَ فَقَالَ أُوصِيكَ بِوَصِيَّةٍ فَاحْفَظْهَا لا تَشْتَرِيَنَّ شَيْناً وَلا عَيْباً وَاسْتَوْثِقْ مِنَ الْعُهْدَةِ.
18. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from Muhammad ibn ‘Abd al-Hamid from abu Jamilah who has said the following: “Once I visited abu ‘Abd Allah (a.s.), and he asked, ‘Young man, what you do for a living?’ I replied, ‘It is slaves.’ He (the Imam) said, ‘I recommend you so keep my recommendations safe. You must not buy physically or morally defective ones. You must make the guarantees strong and firm.’”