Mishkat al-Masabih 30 Fine Qualities كتاب المناقب 37

وَعَنْ أَنَسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَثَلُ أَصْحَابِي فِي أُمَّتِي كَالْمِلْحِ فِي الطَّعَامِ لَا يَصْلُحُ الطَّعَامُ إِلَّا بِالْمِلْحِ» قَالَ الْحَسَنُ: فَقَدْ ذَهَبَ مِلْحُنَا فَكَيْفَ نصلح؟ رَوَاهُ فِي «شرح السّنة»

Anas reported God’s messenger as saying, “Among my people my companions are like salt in food, for food is good only when there is salt in it.” Al-Hasan[*] said, “Our salt has gone, so how can we be good?” *i.e., Al Hasan al Basri. It is transmitted in Sharh as-sunna .