O ye who believe! Stand out firmly for Allah, as witness to fair dealing, and let not the hatred of others to you make you swerve to wrong and depart from justice. Be just: that is next to Piety: and fear Allah. For Allah is well-acquainted with all that you do.[Qur'an 5:8]

Narrated Abu Huraira(RA):A man came to the Prophet(PBUH) and demanded a camel (the Prophet owed him). Allah's Apostle told his companions to give him (a camel). They said, "We do not find except an older camel (than what he demands). (The Prophet ordered them to give him that camel). The man said, "You have paid me in full and may Allah also pay you in full." Allah's Apostle said, "Give him, for the best amongst the people is he who repays his debts in the most handsome manner."