It is narrated from Sayyiduna Ali (may Allah be pleased with him), through Safwan bin Abdullah or Abdullah bin Safwan, that on the day of the Battle of Siffin a man cursed, saying: "Allahumma il'an ahl al-Sham" (O Allah, curse the people of Syria). Sayyiduna Ali (may Allah be pleased with him) (rebuking him) said: "Do not revile the people of Syria in general (or as a whole), for among them are the Abdal (the chosen friends of Allah)." He (may Allah be pleased with him) repeated this sentence three times.
Imam Ahmad recorded it as marfu' in the 'Musnad of Ali (may Allah be pleased with him)'.
Also, al-Nadr narrated something similar through Salih bin Abi al-Akhdar from Ibn Shihab al-Zuhri, from Safwan bin Abdullah, from Sayyiduna Ali (may Allah be pleased with him).
Imam al-Dhuhli recorded it in "Ilal Hadith al-Zuhri" with the chain of Muhammad bin Kathir, Ma'mar and al-Zuhri, through Safwan bin Abdullah bin Safwan.
It has a supporting report (shahid) also narrated as mawquf from Sayyiduna Ali (may Allah be pleased with him) through the chain of Ibn Zurayr al-Ghafiqi, which Imam Ibn Yunus recorded in "Tarikh Misr".
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب الرقائق / 3197
Hadith Gradingمحدثین:إسناده صحيح
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :الأثر بهذا الإسناد صحيح. » «أخرجه الأحاديث المختارة للضياء برقم: 485، وأخرجه المستدرك للحاكم برقم: 8755، وأخرجه المطالب العالية لابن حجر برقم: 3197 / 3، وأخرجه مصنف عبد الرزاق برقم: 20455، وأخرجه المعجم الأوسط للطبراني برقم: 291»