In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Allaah [The Most High] said:
يُرِيدُونَ أَن يُطۡفِـُٔواْ نُورَ ٱللَّهِ بِأَفۡوَٲهِهِمۡ وَيَأۡبَى ٱللَّهُ إِلَّآ أَن يُتِمَّ نُورَهُ ۥ وَلَوۡ ڪَرِهَ ٱلۡكَـٰفِرُونَ
They want to extinguish Allaah’s Light with their mouths (i.e. the Qur’an, the pure Islamic monotheism and the guidance Allaah sent Muhammad with) but Allah will not allow except that His Light should be perfected even though the disbelievers hate (it). [Soorah At-Tawbah: Ayah: 32]
They want to extinguish what Allaah sent His Messenger with- the guidance and the religion of truth- merely by way of their arguments and fabrications. So their example in this [instance] is that of one who wants to extinguish the light of the sun or the moon by blowing at [them] and this can never be achieved. [Source: An Excerpt from ‘Al-Misbaah Al-Muneer Fee Tahdeeb Tafseer Ibn Katheer’. Slightly paraphrased]