Shaqiq relates: I heard Sayyiduna Sahl bin Hunayf (may Allah be pleased with him) say at Siffin: "O people! Hold your opinion suspect. By Allah! I saw myself on the day of Abu Jandal; had I been able to turn back the decision of the Messenger of Allah (peace and blessings be upon him), I would certainly have done so. By Allah! We never placed our swords on our shoulders for any matter except that they made the way easy for us towards a matter that we recognised, except for this (present) matter of yours."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 5580