Musnad Ahmad 1153:975

'Affan narrated to us, he said: Al-Qasim ibn al-Fadl narrated to us, he said: Muhammad ibn 'Ali narrated to me, he said: 'A'ishah was in debt, so it was said to her: "What is the matter with you and debt?" She said: "I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: 'There is no servant who has the intention to pay off his debt, except that he has help from Allah, the Almighty and Majestic.' So I am seeking that help."