It is narrated from Sayyiduna Samurah bin Jundub (may Allah be pleased with him); he said: The Messenger of Allah (peace and blessings be upon him) used to say to us: "Soon you will be among the people like salt in food; food is not right without salt."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 7067