Wisdom in da'wah and persuasion

أُو۟لَـٰٓئِكَ ٱلَّذِينَ يَعْلَمُ ٱللَّهُ مَا فِى قُلُوبِهِمْ فَأَعْرِضْ عَنْهُمْ وَعِظْهُمْ وَقُل لَّهُمْ فِىٓ أَنفُسِهِمْ قَوْلًۢا بَلِيغًا

Those are the ones of whom Allāh knows what is in their hearts, so turn away from them but admonish them and speak to them a far-reaching [i.e., effective] word.