As for our equality in (the art of) war and in (numbers of) men, certainly you cannot be more penetrating in doubtfulness (of belief) than I am in certainty (of belief), and the people of Syria are not more greedy for this world than the people of Iraq are for the next world.
As for your saying that both of us are sons of ‘Abd Manāf, it is no doubt so, but Umayyah cannot be like Hāshim, nor Ḥarb like ‘Abd al-Muṭṭalib, nor can Abū Sufyān be like Abū Ṭālib. The muhājir (immigrant) cannot be a match for him who was set free (on the day of fall of Mecca), nor can one of pure descent be a match for him who has been adopted, nor the pursuer of truth be a match of the adherent to wrong, nor a believer be a match for a hypocrite. How bad are the successors who go on following their predecessors who have fallen in the fire of Hell!
Besides that, we also have the distinction of prophethood among us, by virtue of which we subdued the strong and raised up the down-trodden. When Allāh made Arabia enter (the fold of) His religion, and the people submitted to it willingly or unwillingly, you were among those who entered the religion either from greed or from fear, at a time when those who had gone first had preceded and the first muhājirūn had acquired their (peculiar) distinction.
Now, do not allow Satan have a share with you nor let him have his sway over you; and that is an end to the matter.
 During the battle of Ṣiffīn, Mu‘āwiyah thought of again demanding the province of Syria from Amīr al-mu’minīn and to play such a trick as to succeed in his designs. In this connection, he consulted ‘Amr ibn al-‘Āṣ. But the latter did not agree with this idea and said, “O’ Mu‘āwiyah, think a little, what effect will this writing of yours have on ‘Alī? How can he fall in this trap by your persuasion.” On this Mu‘āwiyah said, “We are all descendants of ‘Abd Manāf. What difference is there between ‘Alī and me that he may score over me and I may not succeed in deceiving him?” ‘Amr ibn al-‘Āṣ said, “If you think so, then write and see (the outcome).” Mu‘āwiyah therefore wrote a letter to Amīr al-mu’minīn wherein he made a demand for Syria and also wrote: “We are descendants of ‘Abd Manāf. There is no distinction of one over the other among us.” Then, Amīr al-mu’minīn wrote this letter in reply and mentioning his own predecessors along with those of Mu‘āwiyah disproved his contention of equality. Although the origin of both was the same and the paternal chain of both joined at ‘Abd Manāf, the progeny of ‘Abd Shams was the source of all evil in morality and character and was involved in heresy and vice whereas the house of Hāshim was the worshipper of one God and kept aloof from idolatory. If the branches growing out of the same root bear both flowers as well as thorns, then both cannot be deemed equal. Consequently, it does not need any detailed explanation to show that Umayyah and Hāshim, Ḥarb and ‘Abd al-Muṭṭalib and Abū Sufyān and Abū Ṭālib were not match of each other from any angle. This is not denied by any historian nor by any biographer. In fact, after this reply even Mu‘āwiyah did not dare refute it, because the fact could be concealed that after ‘Abd Manāf it was Hāshim alone who possessed conspicuous prestige among the Quraysh, and the most important positions with relation to the Ka‘bah namely siqāyah (i.e., the superintendence of the water-supply, especially with a veiw to the needs of pilgrims) and rifādah (provisioning of pilgrims) was assigned to him. As such, at the time of ḥajj, caravan after caravan used to come and stay with him and he was such a generous host to them that those who partook of his generosity and benevolence would praise him for long thereafter.
The worthy son of this very large-hearted and courageous father was ‘Abd al-Muṭṭalib whose name was Shaybah and surname was Sayyidu’l-Baṭḥā’ (the Chief of the Valley of Mecca). He was the successor to the distinction of Abraham’s line and owner of the greatness and chiefdom of Quraysh. The high courage and far-sightedness showed by him before Abraham is a shining star of the family of ‘Abd Manāf. ‘Abd Manāf was a pearl and ‘Abd al-Muṭṭalib was the lustre of the pearl.
‘Abd al-Muṭṭalib’s son was Abū Ṭālib whose lap served as the cradle for ‘Abdullāh’s orphan child and the training place of the Prophet. He brought up the Prophet in his care, and shielded him against his enemies. To compare Abū Sufyān, Ḥarb and Umayyah with them or to regard them as their matches is the same as to close one’s eyes to the lustre of light and to regard it as darkness.
After recounting this geneological difference the next point of distinction that Amīr al-mu’minīn has described is that he himself is a muhājir (immigrant from Mecca) while Mu‘āwiyah is a ṭalīq (i.e., one of those whom the Prophet had spared on the day of fall of Mecca). Therefore, when the Prophet entered Mecca victorious he enquired from the Quraysh how they thought he would deal with them, and all said that being a generous son of a generous father they expected only good from him, whereupon the Prophet said, “Go away, you have all been spared.” That is, “you did deserve to be detained as slaves but as a mark of obligation you have been left free.” These spared ones included Mu‘āwiyah and Abū Sufyān also. Thus, Ibn Abi’l-Ḥadīd and ash-Shaykh Muḥammad ‘Abduh have recorded the following note in their annotations to this letter “Abū Sufyān and Mu‘āwiyah both were among the spared ones.” (Ibn Abi’l-Ḥadīd, vol. 17, p. 119; ‘Abduh, vol. 3, p. 17)
The third point of distinction is that Amīr al-mu’minīn’s lineage is pure and clear and there is no doubtful point anywhere. As against this, for Mu‘āwiyah he has used to the word “lasīq”. Men of letters have given lasīq to mean “One who is attributed to other than his father.” In this connection, the first doubt that is entertained about Umayyah is whether he was the son of ‘Abd Shams or only his slave who began to be known as his son because of having been brought up by him. Thus, al-‘Allāmah al-Majlisī has related from Kāmil al-Bahā’ī that:
Umayyah was a Byzantinian slave of ‘Abd Shams. When he found him intelligent and sagacious he freed him and adopted him as his son, as a result of which he began to be called Umayyah son of ‘Abd Shams, as Zayd (ibn al-Hārithah) was called Zayd ibn Muḥammad before the verse was revealed (to prohibit it).(Biḥār al-anwār, 1st ed., vol. 8, p. 383)
The second doubt in the Umayyad lineage is whether Ḥarb who is known as the son of Umayyah was really his son or a slave brought up by him. In this connection, Ibn Abi’l-Ḥadīd has quoted from Abu’l-Faraj al-Iṣbahānī’s book that:
Mu‘āwiyah enquired from the lineage expert Daghfal (Ibn Ḥanẓalah) whether he had seen ‘Abd al-Muṭṭalib and he replied in the affirmative. He further enquired how he found him and Daghfal replied, “He was prestigious, handsome and a man of open forehead, while his face bore the brightness of Prophethood.” Then, Mu‘āwiyah enquired whether he had seen Umayyah ibn ‘Abd Shams also, and he replied that he had seen him too. He enquired how he found him and he replied, “Weak bodied, bent stature and blind in the eyes. In front of him was his slave Dhakwān who led here and there.” Mu‘āwiyah said it was his son Abū ‘Amr (Ḥarb) whereupon he said, “You say so but the Quraysh only know that he was his slave.” (al-Aghānī, vol. 1, p. 12; Sharḥ Nahj al-balāghah, vol. 17, pp. 231-232)
In this connection, the third doubt is about Mu‘āwiyah himself. Thus Ibn Abi’l-Ḥadīd has written that:
Mu‘āwiyah’s mother Hind led a life of vileness and immorality. az-Zamakhsharī (Abu’l-Qāsim Maḥmūd ibn ‘Umar [467/1075 — 538/1144]) has written in his book Rabī‘u’l-abrār that Mu‘āwiyah’s parentage was traced back to four persons who were: Musāfir ibn Abī ‘Amr, ‘Umārah ibn al-Walīd ibn al-Mughīrah, al-‘Abbās ibn ‘Abd al-Muṭṭalib and aṣ-Ṣabbāḥ (a singer for ‘Umārah). (Sharḥ Nahj albalāghah, vol. 1, p. 336)
The fourth point of distinction that Amīr al-mu’minīn has stated is that he himself was the devotee of right while Mu‘āwiyah was the devotee of wrong and this fact needs no proof, for the whole life of Mu‘āwiyah was spent in suppressing right and hankering after wrong. No where is his step seen advancing towards right.
The fifth distinction that Amīr al-mu’minīn has mentioned is that he himself was a believer whereas Mu‘āwiyah was a mischief-monger and a hypocrite. Just as there can be no doubt about Amīr al-mu’minīn’s belief, there can be no doubt about Mu‘āwiyah’s mischief-mongering and hypocricy. Thus, Amīr al-mu’minīn has exposed his hypocricy in the earlier writing in these words.
These people had not accepted Islam but they had secured safety by verbally professing it and had hidden their misbelief. Consequently, when they found helpers for their mischief they disclosed it.