Imam Ali did not treat opponents and rebels the same way
Another characteristic of that great Imam (a.s.) was that he did not behave in the same way towards all of his opponents and enemies. He did not use the same method for all of them. He differentiated between different individuals and orientations. Ali (a.s.) stood firm against the faithless Khawarij. Of course, he stood up against their deviation, wrongdoings and reliance on the outward aspects of religion.
He stood against Muawiyah as well. When they put the Holy Quran on their spears, the Commander of the Faithful said, "By Allah, this is a trick and deception. They do not believe in the Holy Quran". And when Khawarij confronted him with their reliance on the outward aspects of religion - they recited the Holy Quran in a plaintive and sad tone in front of the Commander of the Faithful (a.s.) - Hazrat stood up against them.
That is to say, the Commander of the Faithful (a.s.) stood up against those people who wanted to move forward on the basis of the outward aspects of religion and it did not matter to him whether he was confronting Muawiyah or Khawarij. Nonetheless, he did not behave towards them in the same way. He showed resistance, but in general, his method was to offer advice.
This was the reason why he said, "Do not fight Khawarij after me because one who seeks right but does not find it, is not like one who seeks wrong and finds it". Those who are after truth, but who make a mistake on this path - such people are after the truth, but they make a mistake because of their ignorance and reliance on superficial things - are not like those who are after evil and who find it. Such people are not the same.