If the intent behind carrying a copy of the Qur’aan in one’s pocket or car is to make use of it when possible, by reading it during one’s free time, this is undoubtedly a good deed which one will be rewarded for. All things are by their intentions, however. If this is his purpose and goal, and the Qur’aan is not exposed to any misuse or disrespect, this is fine. As for carrying it to repel harm and devils, then the Qur’aan was not revealed for this, and this is an innovation and is not permissible. Holding such beliefs is impermissible. Yes, the Speech of Allaah is Healing, and the Speech of Allaah is beneficial wherever it is found and wherever it is recited. Carrying it for the aforementioned purpose, however, is an impermissible innovation. The Qur’aan is to be recited at all times and places, excluding the exceptional times like during a woman’s menses or post-natal bleeding, or the exceptional places like sites for rubbish and filth. Reciting the Qur’aan is of the best of deeds, the greatest of acts which bring the servant closer to his Lord, and the most supreme means of remembering Allaah. The Muslim must pay attention, and show reverence, to the Book of Allaah. If he recites from what he has memorized by heart, this is good. Yet many of the scholars prefer reading from the Mus-haf.
As for reading or reciting the Qur’aan in order to repel harm or the devils, then the Qur’aan is Healing, and there is no doubt that remembering Allaah does repel the devils. Whoever recites Aayah Al-Kursee at night will be protected from the Devils until morning, as found in the Hadeeth of Abee Hurayrah (Bukhaary 2311. Simply carrying the Mus-haf for this purpose, however, is not sufficient, and the Qur’aan was not revealed for this purpose. As for hanging from the car’s mirror and the likes, there is no doubt that this is disrespect towards the Qur’aan and is impermissible.