Sayyiduna Awf bin Malik (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) judged between two men, and the one against whom judgement was given said: Hasbiyallahu wa ni'ma al-wakil (Allah is sufficient for me, and He is the best Disposer of affairs). The Prophet (peace and blessings be upon him) said: "Bring him back," or he said: "Bring the man to me." Then he said: "Allah praises prudence and resourcefulness and blames helplessness and lack of effort; and when something," or he said: "a matter, overwhelms you, then say: Hasbiyallahu wa ni'ma al-wakil (Allah is sufficient for me, and He is the best Disposer of affairs)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15188