Letter 37: To Muawiyah
ومن كتاب له (عليه السلام)
Glory be to Allah! How staunchly you cling to innovated passions and painful bewilderment along with ignoring the facts and rejecting strong reasons which are liked by Allah and serve as pleas for the people. As regards your prolonging the question of 'Uthman's 1 murder the position is that you helped 'Uthman when it was really your own help while you forsook him when he was in need of help; and that is an end to the matter.
فَسُبْحَانَ الله! مَا أَشَدَّ لُزُومَكَ لِلاْهْوَاءِ 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.
'Uthman after he had been killed, although when he was surrounded and clamoured for his help by writing letter after letter Mu'awiyah never budged an inch. However, just to make a show he had sent a contingent towards Medina under Yazid ibn Asad al-Qasri, but had ordered it to remain in waiting in the valley of Dhu Khushub near Medina. Eventually, 'Uthman was murdered and he went back with his contingent. No doubt Mu'awiyah wished 'Uthman to be killed so that he should create confusion in the name of his blood and through these disturbances clear the way for allegiance to himself (as Caliph). That is why he neither helped him when he was surrounded nor thought it necessary to trace the murderers of 'Uthman after securing power.
There is no question of denying that Mu'awiyah claimed to help ↩