Allah says, interpretation of meaning,
(By the mercy of Allah – O Prophet, you were gentle with them. And if you had been ill-mannered and hard-heated, they would have deserted you.)
This aya contains factors of the prophetic message’s success, principles of Islamic ruling, and methodology of behavior with people. The first factor is that the Prophet (saaw) had a gentle, merciful heart, encompassing all people. Allah, be exalted, had made His prophet easy-going, amenable, and very compassionate. If he had been ill-mannered and hard-hearted, people would have had deserted him. However, Allah sent him as a merciful gift to all men. He also made him a role model in ethics and behavior. Of these factors, Allah commanded His prophet to abide by, is to forgive his people mistakes, and not pay them back their ill-treatment with him; rather, he would meet wrongdoing with kindness, and he would ask Allah to forgive them for their mistakes. (At-Tafsîr al-Wasît, Az-Zuhyly, Wahba Mustafa).