No Muslim would abandon Islam through sound reasoning
No period of history, from the Age of Happiness until now, tells us that a Muslim has preferred another religion over Islam with their sound reasoning or entered that religion based on sound proof. It is true that there have been some who have left Islam; but this has been through imitation and is of no importance. However, the followers of other religions have continuously entered the fold of Islam in throngs based on sound proof and through sound reasoning. If we demonstrate true Islam and the truth and uprightness that befit Islam, people will continue to enter it in greater numbers.
History also shows us that the development and civilization of Muslims is proportionate to their adherence to the truth of Islam, while the development and civilization of others is inversely proportionate to their religion. Also, the truth informs us that the awakening of humankind cannot be without religion. Particularly, a person who has awakened to the truth, who has come to know true humanity, and has become a candidate for the future and eternity, cannot be so without religion. For the awakening of humankind cannot occur unless it obtains the point – the nucleus of truth, i.e., the true religion – on which it will rely against the onslaughts from the universe and from which it will seek help in order to blossom its infinite ambitions and aspirations. It is because of this reality that an inclination has awakened in everyone to search for the true religion. This gives the glad tiding that humanity will naturally adopt Islam in the future.
O unfair ones! How and why do you find Islam, which has the capacity to embrace, unite, nurture, and enlighten the entire world, so narrow that you have assigned it to the poor and certain bigoted hojas, excluding half of its followers? Why and how do you dare imagine that the light filled palace of Islam, which has all perfections and contains the material that will nourish the elevated feelings of all of humankind, belongs exclusively to some poor people, Bedouins, and reactionaries, as if it were a mournful, black tent? It is a fact that everyone sees and follows whatever is reflected in their mirror. This means that your dark and lying mirror shows it to be like that.
(From Munazarat [“Discussions”])
Bediuzzaman Said Nursi