Narrated `Abdullah bin `Abbas: Abu Sufyan told me that Heraclius said to him, "When I inquired you what he (i.e. Muhammad) ordered you, you replied that he ordered you to establish the prayer, to speak the truth, to be chaste, to keep promises and to pay back trusts." Then Heraclius added, "These are really the qualities of a prophet."

Narrated Abu Huraira: Allah's Apostle said, "The signs of a hypocrite are three: (1) whenever he speaks, he tells a lie, (2) whenever he is entrusted, he proves to be dishonest, (3) whenever he promises, he breaks his promise.

Narrated Muhammad bin `Ali: Jabir bin `Abdullah said, "When the Prophet died, Abu Bakr received some property from Al-`Ala bin Al-Hadrami. Abu Bakr said to the people, "Whoever has a money claim on the Prophet, or was promised something by him, should come to us (so that we may pay him his right)." Jabir added, "I said (to Abu Bakr), Allah's Apostle promised me that he would give me this much, and this much, and this much (spreading his hands three times)." Jabir added, "Abu Bakr counted for me and handed me five-hundred (gold pieces), and then five-hundred, and then five-hundred."

Narrated Sa`id bin Jubair: A Jew from Hira asked me which one of the two periods Musa (i.e. Prophet Moses) completed. I said, "I don't know, (but wait) till I see the most learned 'Arab and inquire him about it." So, I went to Ibn `Abbas and asked him. He replied, "Moses completed the longer and better period." Ibn `Abbas added, "No doubt, an apostle of Allah always does what he says."