Musnad Ahmad

It is narrated from Hazrat Naeem bin Nahham (may Allah be pleased with him) that once, on a very cold night, the muezzin began the call to prayer. I was lying in my blanket, wishing that he would announce, "Pray in your tents." When he reached "Hayya 'ala al-falah," he made the announcement, "Pray in your tents." Later, I asked him about this, and he told me that the Prophet (peace and blessings be upon him) himself had instructed him to do so.

It is narrated from Hazrat Naeem bin Nahham (may Allah be pleased with him) that once, on a very cold night, the muezzin began the call to prayer. I started wishing in my blanket that he would announce, "Pray in your tents." When he reached "Hayya 'ala al-Falah," he made the announcement that there is no sin upon the one who prays in his own tent.