ادْعُ إِلَىٰ سَبِيلِ رَبِّكَ بِالْحِكْمَةِ وَالْمَوْعِظَةِ الْحَسَنَةِ ۖ وَجَادِلْهُم بِالَّتِي هِيَ أَحْسَنُ ۚ إِنَّ رَبَّكَ هُوَ أَعْلَمُ بِمَن ضَلَّ عَن سَبِيلِهِ وَهُوَ أَعْلَمُ بِالْمُهْتَدِينَ

The preacher’s call to the Truth is a process which emerges out of intense feelings of sincerity, seriousness and well-wishing. The realization of a man that he is answerable to God forces him to issue such a call to the subjects of God. He does so because he thinks that if he does not, he himself will be caught on the Day of Judgement. The natural result of such thinking is that the preacher speaks words of wisdom, gives good advice and engages in serious discussion. Exhortations to accept the Truth can be effective only when they are supported by argument and reasoning, and when they take into account the mentality of the addressees. A reasoned discourse should readily convince them of the reality of things but if it ignores their intellectual capacity, it will miss the mark and will do nothing to bolster the status of the preacher. Sympathy is a characteristic which develops in a discourse due to a well-wishing mentality (al-mu‘izah al-hasanah). When the preacher whose personality has been radically transformed by his realization of God’s majesty and glory speaks about God, the majesty of God will definitely shine through his discourse. The messenger of God who, after seeing heaven and hell, comes forward to show them to others will certainly in his discourse give glimpses of the joys of heaven and the terror of hell. The combination of these features will make his discourse so effective that it will melt hearts and bring tears to the eyes. Wisdom and good counselling are the staff of dawah work. However there are always those addressees who indulge in pointless discussions with the intention, who have no desire to understand the message but they only want to complicate matters. In such a case, the preacher must respond with gentleness; in the face of harsh words he must resort to reasoning and analysis and, in response to provocation, he must exercise patience. The eye of one who calls on others to the Truth is not on his audience but on God, who transcends all. Therefore, he utters such statements as prove to be true in God’s eyes rather than in man’s assessment.

— Source: Tazkirul Quran (Maulana Wahiduddin Khan) via Quran.com (16:125)