Authentic
hadith of Sahih Muslim
Sahih Muslim 715ac
وَحَدَّثَنِيهِ مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا عَبْدُ الرَّحْمَنِ، حَدَّثَنَا سُفْيَانُ، بِهَذَا الإِسْنَادِ قَالَ عَبْدُ الرَّحْمَنِ قَالَ سُفْيَانُ لاَ أَدْرِي هَذَا فِي الْحَدِيثِ أَمْ لاَ . يَعْنِي أَنْ يَتَخَوَّنَهُمْ أَوْ يَلْتَمِسَ عَثَرَاتِهِمْ .
This tradition has been reported through anothee chain. 'Abdurahman, one of the sub-narrators, said "I do not know if it in the hadith or not", meaning (the words) "doubting their fidelity and spying into their lapses."
Reported by Muslim (No. 715ac).