Alqamah (may Allah have mercy on him) said: A Bedouin met Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) while we were with him, and said: Al-salamu alayka (peace be upon you), O Abu Abd al-Rahman! He laughed and said: "Allah and His Messenger have spoken the truth. I heard the Messenger of Allah (peace and blessings be upon him) say: The Hour will not be established until the greeting of salam is given only on the basis of acquaintance - and this man recognised me from among all of you, so he greeted me - and until the mosques are taken as thoroughfares in which no prostration is made to Allah, and until a young man sends an old man as a messenger between the two horizons (on a long journey), and until the merchant travels between the two horizons yet finds no profit."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 9457