Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrated: We were with the Messenger of Allah (peace and blessings be upon him) and we were held back from (offering) the Zuhr, Asr, Maghrib and Isha prayers. That weighed heavily upon us, and we said: We are with the Messenger of Allah (peace and blessings be upon him) and in the path of Allah. Then the Messenger of Allah (peace and blessings be upon him) ordered Sayyiduna Bilal (may Allah be pleased with him), and he called the iqamah, and we prayed each time the iqamah was called. Then he (peace and blessings be upon him) said: "There is no group on the earth other than you remembering Allah."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10245