The Muslim is Honest and Truthful in All His Affairs

From Abu Hurairah (radiyallaahu 'anhu) who said that Allaah's Messenger (salallaahu 'alaihi wa'sallam) said: Three things are the sign of the hypocrite: when he speaks he tells lies, when he promises he breaks it and when he is trusted he proves to be dishonest.

So he is truthful and honest in his speech, faithful to his promise, trustworthy in carrying out that which he has been entrusted with. He does not deceive or defraud, he does not tell lies and is not guilty of hypocrisy. So truthfulness and honesty is one of the chief good qualities, whereas falsehood is the head of corruption and evil. So his honesty keeps him far away from evil and foul deeds and sickness of the heart. Therefore whatever action he does, he does it for Allaah, the One free and far removed from all defects, not to attain some worldly position, fame or repute.