'Uqbah bin 'Amir (may Allah be pleased with him) says: I submitted, "O Messenger of Allah! We pass by people who neither host us nor fulfill the right that is due to us, and we do not take anything from them." The Messenger of Allah (peace and blessings of Allah be upon him) said: "If they do not give except that you take from them by force, then take it by force." Imam Tirmidhi says:
1- This hadith is Hasan (good).
2- It has also been narrated by Layth bin Sa'd from Yazid bin Abi Habib (as is in the chain of Bukhari).
3- The meaning of this hadith is that when the Companions would go out for jihad, they would pass by a people where they would not find food to buy at a price. The Prophet (peace and blessings of Allah be upon him) said: "If they refuse to sell (food) except that you take it by force, then take it by force."
4- In another hadith, a similar clarification has come. It is narrated from 'Umar bin Khattab (may Allah be pleased with him), he also used to give a similar ruling. 1