Explaining the treaty to the people
أَيُّهَا النَّاسُ إِنَّكُمْ لَوْ طَلَبْتُمْ مَا بَيْنَ جَابُلْقَا وَجَابِرْسَا رَجُلًا جَدُّهُ رَسُولُ اللَّهِ مَا وَجَدْتُمْ غَيْرِي وَغَيْرَ أَخِي، وَإِنَّ مُعَاوِيَةَ نَازَعَنِي حَقّاً هُوَ لِي فَتَرَكْتُهُ لِصَلَاحِ الْأُمَّةِ وَحَقْنِ دِمَائِهَا.Reference: Ibn Shahrashub, al-Manaqib (1379 AH ed.), vol. 4, p. 34 [Ibn Shahrāshūb] [WikiShia]
Arabic as quoted in the cited reference work.
He points out that nowhere in the world is there anyone whose grandfather is the Messenger of God (s) apart from himself and his brother. He explains that Mu‘awiya contested a right that belonged to him, and that he gave it up for the good of the community and to prevent bloodshed.