Sayyiduna Usamah bin Sharik (may Allah be pleased with him) said: We were with the Prophet (peace and blessings be upon him) when many Bedouins came from here and there, and the people fell silent, with no one speaking except them. They said: O Messenger of Allah, is there any harm upon us in such-and-such? (These questions were) about people's affairs in which there was no harm. He (peace and blessings be upon him) said: "O servants of Allah, Allah has removed harm, except for the one who unjustly wrongs someone; he is the one who has fallen into harm and is ruined." They said: O Messenger of Allah, is there any harm upon us in seeking medical treatment? He (peace and blessings be upon him) said: "O servants of Allah, seek treatment, for Allah, the Mighty and Majestic, has not placed any disease without also placing its remedy, except old age." The people said: O Messenger of Allah, what is the best thing a person has been given? He (peace and blessings be upon him) said: "Good character."
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 461