It is narrated from Sayyiduna Iyad bin Himar (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said in his sermon: "Allah, the Mighty and Majestic, has revealed to me that you should be humble, so that no one boasts over another and no one transgresses against another."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15070