How can one overcome the whispering of doubt regarding the authenticity of religious texts and their meanings, especially the Prophetic hadiths, and the certainty of the preservation of the Holy Quran, taking into consideration the methodology of Ahl al-Sunnah wa al-Jama'ah concerning Ahadith Ahad (single-chain narrations)?

The cure for satanic whispers (waswas) is to turn away from them and not pay them any heed. The Holy Quran is preserved by Allah Almighty's protection, as He said: "Indeed, it is We who sent down the Dhikr (the Quran), and indeed, We will be its Guardian." No one has ever said that this preservation is exclusive to the Prophet, peace be upon him. The compilation of the Quran during the eras of Abu Bakr and Uthman confirms its preservation from any alteration or distortion. As for the hadiths in the Two Sahihs (Bukhari and Muslim), the majority of them convey certain knowledge and establish their authenticity beyond doubt. One must strive against the self and not yield to these whispers.