Is gentleness required, or strictness, when calling people to Allah?

Question:
May Allah reward you with good and do you good. How should the caller’s invitation be, with gentleness or with strictness? If the caller’s speech is harsh because he is calling to fight the Dajjal and the people, is he correct? And how was the Prophet’s (peace and blessings be upon him) invitation? Was it all gentleness, or sometimes strictness and sometimes gentleness? Describe it for us. May Allah reward you with good.

Answer:
As for the general call, it is to be with strong, weighty words, and with some impactful speech that affects the listeners. It includes some warning, fear, and threat to those who oppose, because this is more effective in making an impact. The Prophet (peace and blessings be upon him), when he delivered the sermon, his eyes would redden, his voice would rise, and his anger would intensify until he was like a warner of an army, saying, “May your morning and evening be [a time of warning].” And he would say, “As for what follows, the best of speech is the Book of Allah, and the best of guidance is the guidance of Muhammad (peace and blessings be upon him).” So every religious innovation (bid'ah) is misguidance. And in another narration, every misguidance is in the Fire.
So as for sermons and general speech delivered to the general public, it should have strength, weightiness, and impact, because this is more effective in making an impact and arousing people’s attention. As for the call to individuals, it is to be with gentleness and wisdom. With the ignorant and those who are not defiant, it is to be with wisdom and good exhortation. And if debate is required, he debates in the best manner. This is how the Prophet (peace and blessings be upon him) called people, because Allah commanded him to do so in His saying, the Exalted: . Yes.