Humility is one of the greatest blessings that Allaah can bestow upon His slave. He says (interpretation of the meaning):
"And by the Mercy of Allaah, you dealt with them gently. And had you been severe and harsh-hearted, they would have broken away from about you" [Aal 'Imraan 3:159]
"And verily, you (O Muhammad) are on an exalted (standard of) character" [al-Qalam 68:4]
This refers to the Prophet (peace and blessings of Allaah be upon him) being a true slave of Allaah in many ways and his treating all people with the utmost kindness. His character was one of complete humility based on sincerity towards Allaah and compassion towards the slaves of Allaah, which was the complete opposite of the characteristics of the proud and arrogant.