Sayyiduna Abu Madinah al-Darimi (may Allah be pleased with him), who had the honor of being a Companion, states: "When two men from among the Companions of the Prophet (peace and blessings be upon him) met each other, they would not part until one of them had recited before the other: 'By time! Indeed, mankind is in loss.'"
Al-Tabarani recorded it in al-Mu'jam al-Awsat, and its narrators are the narrators of the Sahih.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الزهد / 17723