Sahih Muslim Vol. 1, Book of Introduction, Hadith 26
Hasan bin ur-Rabī’ narrated to us, Hammād bin Zayd narrated to us, on authority of Ayyūb and Hishām [bin Hassān], on authority of Muhammad [bin Sīrīn] ; and Fuḍayl [bin Īyāḍ] narrated to us on authority of Hishām [bin Hassān]; he said Mukhlad bin Husayn narrated to us, on authority of Hishām [bin Hassān], on authority of Muhammad bin Sīrīn , that he said:
‘Indeed this knowledge is faith, so carefully consider from whom you take your faith’.
حَدَّثَنَا حَسَنُ بْنُ الرَّبِيعِ، حَدَّثَنَا حَمَّادُ بْنُ زَيْدٍ، عَنْ أَيُّوبَ، وَهِشَامٍ، عَنْ مُحَمَّدٍ، وَحَدَّثَنَا فُضَيْلٌ، عَنْ هِشَامٍ، قَالَ وَحَدَّثَنَا مَخْلَدُ بْنُ حُسَيْنٍ، عَنْ هِشَامٍ، عَنْ مُحَمَّدِ بْنِ سِيرِينَ، قَالَ إِنَّ هَذَا الْعِلْمَ دِينٌ فَانْظُرُوا عَمَّنْ تَأْخُذُونَ دِينَكُمْ .