Sayyiduna Qabisah bin Mukhariq al-Hilali (may Allah be pleased with him) says: I took upon myself a debt (to settle a dispute), so I came to the Prophet (peace and blessings be upon him) to ask him about it. He said: "Stay, O Qabisah, until the charity comes to us, and we will order it for you." Then the Messenger of Allah (peace and blessings be upon him) said: "O Qabisah! Asking is not lawful except for one of three: a man who has taken upon himself a debt (to settle a dispute), so asking is lawful for him until he obtains it, then he refrains; a man struck by a calamity that destroys his wealth, so asking is lawful for him until he obtains what will support his living (or he said: what will meet his needs); and a man struck by poverty, until three men of sound judgement from his people say: So-and-so has been struck by poverty; then charity is lawful for him until he obtains what will support his living or meet his needs. Apart from these, O Qabisah, asking is unlawful (suht), and the one who does it consumes it as unlawful wealth."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13194