Al-Muwatta Hadith 58.11

Yahya related to me from Malik from Zayd ibn Aslam from Ata ibn Yasar that a man of the Banu Asad said, "My family and I dismounted to rest at Baqi. My family said to me, 'Go to the Messenger of Allah, may Allah bless him and grant him peace, and ask him for something that we can eat,' and they began to mention their need. I went to the Messenger of Allah, may Allah bless him and grant him peace, and found that a man was asking for something, and the Messenger of Allah, may Allah bless him and grant him peace, was saying, 'I do not have anything to give you.' The man turned away from him in anger, saying, 'By my life! You give to whomever you wish.' The Messenger of Allah, may Allah bless him and grant him peace, said, 'He is angry with me because I do not have anything to give him. Whoever asks of you while he has an uqiya or its like, has asked with importunity.' " The man continued, "I said to myself about a camel that we had, 'It is better than an uqiya.' (Malik explained that an uqiya was forty dirhams.) So I returned and did not ask him for anything, and the Messenger of Allah, may Allah bless him and grant him peace, sent me barley and raisins after that. He gave us from his share until Allah, the Mighty, the Majestic gave us relief."