Sahih al-Bukhari 3607
Sahih al-Bukhari · Book 61: Virtues and Merits of the Prophet (pbuh) and his Companions · The signs of Prophethood in Islam
Narrated Hudhaifa:
حَدَّثَنِي مُحَمَّدُ بْنُ الْمُثَنَّى ، قَالَ حَدَّثَنِي يَحْيَى بْنُ سَعِيدٍ ، عَنْ إِسْمَاعِيلَ ، حَدَّثَنِي قَيْسٌ ، عَنْ حُذَيْفَةَ ـ رضى الله عنه ـ قَالَ تَعَلَّمَ أَصْحَابِي الْخَيْرَ وَتَعَلَّمْتُ الشَّرَّ.
My companions learned (something about) good (through asking the Prophet) while I learned (something about) evil.