A: Yes, I advise all my Muslim brothers, the scholars and Du'ah (callers to Islam) to adopt good manners and leniency in Da'wah, especially in the controversial issues when debating and studying them. I would ask them not to let enthusiasm and intensity make them say what should not be said, as this causes division, discord, mutual hatred, and disunity. Instead, the Du'ah, teachers, and guides should use beneficial methods and leniency when speaking, in order for their words to be accepted and to not make people avoid them.
And by the Mercy of Allâh, you dealt with them gently. And had you been severe and harshhearted, they would have broken away from about you
And speak to him mildly, perhaps he may accept admonition or fear (Allâh).
Invite (mankind, O Muhammad ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭ ﺳﻠﻢ) to the Way of your Lord (i.e. Islâm) with wisdom (i.e. with the Divine Revelation and the Qur'ân) and fair preaching, and argue with them in a way that is better.
And argue not with the people of the Scripture (Jews and Christians), unless it be in (a way) that is better (with good words and in good manner, inviting them to Islâmic Monotheism with His Verses), except with such of them as do wrong
Kindness does not become a part of anything without adorning it, and is not withdrawn from anything without marring it.
Anyone who is deprived of kindness is deprived of all good.
The Du'ah and teachers should utilize beneficial methods and beware of strictness and harshness, because this might lead to rejection of AlHaqq (the Truth), widening the gap of disagreement, and disunity among Muslims, although their aim is to clarify AlHaqq, encourage acceptance of it, and to benefit people from their Da'wah. The aim is not to demonstrate your knowledge, that you are calling to Allah or that you are jealously protective of the Din (religion of Islam), as Allah knows the secret and that which is yet more hidden. The aim is to spread Da'wah and benefit people through your advice. You should, therefore, seek to help people accept your advice and be cautious against what may cause them to repulse it and refuse to accept it.