Prophet Muhammad (peace be upon him) says: I am amazed to the character of the believer...all his matches are good for him...if something good befalls him will be good for him and he'll be happy, he's happy for it something good came from Allah (Subhan Wa Talaa'a) to me I am happy and this is something understandable by everyone then the Prophet Muhammad (peace be upon him) says the amazing part is and if something harmful befalls that believer, he has patience for the sake of Allah and this one makes me to be so amazed from the believer and this character that he's happy when something good comes from Allah to him so he thanks Allah in return and when something bad or harmful befalls him so he has patience for the sake of Allah. This particular character is a character and only a character for the believer that made the Prophet (peace be upon him) to say I am amazed.
You don't see that character in anyone else besides the believer. You don't see that character when someone Allah gives him or provides him or sustains him or something good he says Alhamdulillah, this is from the pleasure of Allah and when something harmful befalls him he says Alhamdulillah I will have patience. This is only a character of a believer.
Anyone who has no imaan or anyone who is not from amongst the believers and when something good comes to him he says this is from me, from my own sweat, from my own hardships, from my own sacrifice and when something harmful comes on him he blames everyone on the surface of this world including Allah except himself. Yes this is the character of who? This is the character of the non-believer.
When something good comes to him from Allah (azzawajal) he might thank everyone except Allah (subhanawa taala) and who sustained him (Allah)... Who gave him (Allah)... Who provided for him (Allah) and when something harmful comes to him even if it's from his own hand, he blames everyone including Allah except himself.
Prophet Muhammad (peace be upon him) says that the character of the believer amazes me. Something good comes to him (Alhamdulillah) this is from Allah and something harmful comes to him, he has the patience for the sake of Allah and waits for his rewards from Allah.