Prophet Muhammad was the most honest person in Makkah, Quraish trusted him for his honesty, he never betrayed them even when they were hostile towards him. The biggest trust he was assigned was delivering the Message of Islam to humanity.

He was so keen on preserving the attribute of honesty to the point that he used to supplicate saying: “O Allah! I seek refuge with You from sin and debt.” When the Prophet, Peace Be upon Him, was asked why he says this supplications a lot, he said: “Whoever gets into debt speaks and lies, and makes a promise and breaks it.” [1]

The Prophet, Peace Be upon Him, said: “Delay in payment by a rich man is injustice, but when one of you is referred for payment to a wealthy man, let him be referred.” [2]

The Prophet, PBUH, also used to seek refuge in Allah from treachery, describing it as an evil hidden trait: “O Allah, I seek refuge in You from hunger, for it is an evil bed-fellow, and I ask refuge in You from treachery, for it is an evil hidden trait.”

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[1] http://www.heartsactions.com/ref/bt.htm

[2] Muhammad Abu Sinna, Honesty, available on: http://www.alminbar.net/alkhutab/khutbaa.asp?mediaurl=2484

[3] Narrated by Abu Hurayrah, Hadith Sahih, authenticated by al-Albani.