It is narrated from Hazrat Awf (may Allah be pleased with him) that once the Holy Prophet (peace and blessings be upon him) decided a case between two men. The one against whom the decision was made, while returning, said, "Hasbiyallahu wa ni'mal wakeel." The Holy Prophet (peace and blessings be upon him) said, "Call that man back to me and ask him what he just said." He replied, "I said, 'Hasbiyallahu wa ni'mal wakeel.'" The Holy Prophet (peace and blessings be upon him) said, "Allah reproaches foolishness; you should act with wisdom. Even then, if you are overpowered, then say, 'Hasbiyallahu wa ni'mal wakeel.'"
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 23983
Hadith Gradingحکم دارالسلام:إسناده ضعيف لضعف بقية ، وجهالة سيف