What is the ruling on one who denies that the Qur’an is valid for all times and places and casts doubt upon it?

You have uttered a great and reprehensible word. Whoever believes that he can deviate from what is in the Book of Allah, and that he is not bound to act upon it, has disbelieved in Allah the Almighty. This is because Allah has made the Quran a constitution for the Ummah and a methodology for people's lives until the Day of Judgment. Allah says: "Is it the judgment of [the time of] ignorance they desire? And who is better than Allah in judgment for a people who are certain [in faith]." (Quran 5:50). And He says: "And He shares not His legislation with anyone." (Quran 18:26). And He says: "But no, by your Lord, they will not believe until they make you, [O Muhammad], judge concerning that over which they dispute among themselves and then find within themselves no discomfort from what you have judged and submit in [full, willing] submission." (Quran 4:65). The religion has been perfected, as Allah says: "This day I have perfected for you your religion and completed My favor upon you and have approved for you Islam as religion." (Quran 5:3). Whoever claims a deficiency in it or its unsuitability for governance has belied the Quran, and belying the Quran is disbelief. Thus, Islamic law is suitable for every time, place, and situation. You must repent to Allah from this word. It is not an excuse for you to utter it without believing in its meaning, unless you were compelled.