All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
The scholars differed in opinion about the ruling of turning the pages of the Quran with one’s finger that is wet with saliva if this is not done with the intention of disrespecting the Quran. Some scholars stated that it is prohibited (haraam). Ad-Dusooqi Al-Maaliki said in his commentary, “As regards wetting one’s finger with his saliva with the intention of turning the pages of the Quran: then even though it is prohibited, one should not exaggerate to the point of saying that one who does so becomes Kaafir (disbeliever) or that he apostates by doing so, because he did not intend despising the Quran, which necessitates Kufr (disbelief), by this action.”
Nonetheless, some other scholars are of the view that it is not prohibited. For instance, Al-Bujayrimi, from the Shaafi’i School of jurisprudence, said in his commentary on Sharh Al-Manhaj, “The custom of spitting on the wooden writing board (which was used for teaching Quran in primary schools in the past) in order to remove what is on it is not Kufr; rather, it should not even be prohibited.”
What can be deduced from this is that it is more appropriate and better to avoid doing so. Instead, one should be keen on honoring the symbols of Allah given that Allah praised the one who does so. Allah says (what means): {That [has been commanded], and whoever honors the sacred ordinances of Allah – it is best for him in the sight of his Lord.} [Quran 22:30] Allah also says (what means): {That [is so]. And whoever honors the symbols of Allah – indeed, it is from the piety of hearts.} [Quran 22:32]
Allah knows best.