ومن كتاب له (عليه السلام)
إلى معاوية

فَسُبْحَانَ الله! مَا أَشَدَّ لُزُومَكَ لِلاَْهْوَاءِ الْمُبْتَدَعَةِ، وَالْحَيْرَةِ الْمُتَّبَعَةِ، مَعَ تَضْيِيعِ الْحَقَائِقِ وَاطِّرَاحِ الْوَثَائِقِ، الَّتِي هِيَ لله طِلْبَةٌ، وَعَلَى عِبَادِهِ حُجَّةٌ.

فَأَمَّا إِكْثَارُكَ الْحِجَاجَ فِي عُثْمانَ وَقَتَلَتِهِ، فَإِنَّكَ إِنَّمَا نَصَرْتَ عُثْمانَ حَيْثُ كَانَ النَّصْرُ لَكَ، وَخَذَلْتَهُ حَيْثُ كَانَ النَّصْرُ لَهُ، وَالسَّلاَمُ.

[ A letter to Mu'awiya. ]

Allahu Akbar! How hopelessly you are engulfed in your inordinate and sinful desires, how mercilessly you are swept by such vicious and unholy cravings which misguide you in this life and will bring you to a sad end. You have forsaken the cause of truth and justice and have arrogantly spurned the arguments which are agreeable to Allah and were unacceptable to man.

What do you mean by creating this faction and revolt with pretence of taking revenge on the murderers of Uthman?

The real facts of the case are that during the life of Caliph Uthman, you only went to his help when this action in the end was profitable to you and you could get something out of him, and you refused to help him when he was really in need of you and your support and for which he had frequently requested you.