Sahih Muslim 1785 d
It has been narrated through a different chain of transmitters on the authority of Abu Wa'il who said:
I heard Sahl b. Hunaif say at Siffin: Blame (the hollowness) of your views about your religion. I thought to myself on the day of Abu Jandal that if I could turn down the order of the Messenger of Allah (ﷺ), I would. The situation was so difficult that if we mended it at one place, it was rent at another.
وَحَدَّثَنِي إِبْرَاهِيمُ بْنُ سَعِيدٍ الْجَوْهَرِيُّ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ مَالِكِ بْنِ مِغْوَلٍ، عَنْ أَبِي حَصِينٍ، عَنْ أَبِي وَائِلٍ، قَالَ سَمِعْتُ سَهْلَ بْنَ حُنَيْفٍ، بِصِفِّينَ يَقُولُ اتَّهِمُوا رَأْيَكُمْ عَلَى دِينِكُمْ فَلَقَدْ رَأَيْتُنِي يَوْمَ أَبِي جَنْدَلٍ وَلَوْ أَسْتَطِيعُ أَنْ أَرُدَّ أَمْرَ رَسُولِ اللَّهِ صلى الله عليه وسلم - مَا فَتَحْنَا مِنْهُ فِي خُصْمٍ إِلاَّ انْفَجَرَ عَلَيْنَا مِنْهُ خُصْمٌ ‏.‏