Those who were left behind were glad on account of their sitting behind Allah's Messenger and they were averse from striving m Allah's way with their property and their persons, and said: Do not go forth in the heat. Say: The fire of hell is much severe in heat. Would that they understood (it).

And it does not beseem the believers that they should go forth all together; why should not then a company from every party from among them go forth that they may apply themselves to obtain understanding in religion, and that they may warn their people when they come back to them that they may be cautious?