وَحَدَّثَنِي مَالِكٌ، عَنْ صَفْوَانَ بْنِ سُلَيْمٍ، أَنَّهُ قَالَ قِيلَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم أَيَكُونُ الْمُؤْمِنُ جَبَانًا فَقَالَ ‏"‏ نَعَمْ ‏"‏ ‏.‏ فَقِيلَ لَهُ أَيَكُونُ الْمُؤْمِنُ بَخِيلاً فَقَالَ ‏"‏ نَعَمْ ‏"‏ ‏.‏ فَقِيلَ لَهُ أَيَكُونُ الْمُؤْمِنُ كَذَّابًا فَقَالَ ‏"‏ لاَ ‏"‏ ‏.‏

Malik related to me that Safwan ibn Sulaym said, "The Messengerof Allah, may Allah bless him and grant him peace, was asked, 'Can themumin be a coward?' He said, 'Yes.' He was asked, 'Can the mumin be amiser?' He said, 'Yes.' He was asked, 'Can the mumin be a liar?' Hesaid, 'No.' " Translation Not Available

Book reference: Muwatta Imam Malik Book 56 Hadith 1832
Web reference: Muwatta Imam Malik Book 56 Hadith 19