وَإِذْ أَوْحَيْتُ إِلَى ٱلْحَوَارِيِّنَ أَنْ ءَامِنُوا بِى وَبِرَسُولِى قَالُوٓا ءَامَنَّا وَٱشْهَدْ بِأَنَّنَا مُسْلِمُونَ

It is the dayee who performs the duty of calling upon people to Truth. But a positive response to this call cannot be given unless it is God-inspired. Even after being convinced of the veracity of the call, a man still does not necessarily proceed to accept it, as many impediments still remain—the appearance of the missionary as a common man; the fear that on acceptance of the call the structure of the life already built up will crumble, the question that if this is the Truth, whether certain great men were strangers to the Truth, etc. This is a critical juncture where a man is unable to take a decision, even having reached the stage of decision-making. This is the point at which God helps him. He holds the hands of a person in whom He sees some goodness and leads him across the borders of doubt and ushers him into the area of certainty.

— Source: Tazkirul Quran (Maulana Wahiduddin Khan) via Quran.com (5:111)