What is the ruling on the intrusive thoughts that cause a Muslim to doubt the validity of the Islamic religion and whether Muslims are on the right path, while still believing in Allah, His Messenger, and Islam, and what is the effect of this on his life?

Satan seeks to deter people from acts of obedience and incite them to commit sins. He has sworn to mislead humans and divert them from the straight path. Therefore, a Muslim must not surrender to Satan’s whisperings. Rather, he must learn the true religion, read the texts of revelation, accompany people of uprightness, and avoid isolation, which strengthens Satan’s hold over a person. It is also important to be diligent in prayer and to believe that Islam is the only true religion accepted by Allah, as Allah the Almighty says: "And whoever desires other than Islam as religion - never will it be accepted from him, and he, in the Hereafter, will be among the losers." One must also turn away from satanic whisperings and occupy oneself with reading books of encouragement and deterrence, the biographies of the righteous predecessors, and the stories of the prophets, while supplicating to Allah for success in adhering to the truth and remaining steadfast upon it.