It was narrated from Ibn ‘Umar that the Messenger of Allah ﷺ forbade traveling with the Qur’an to the land of the enemy, lest the enemy gets hold of it.
أَنَّ رَسُولَ اللَّهِ ﷺ نَهَى أَنْ يُسَافَرَ بِالْقُرْآنِ إِلَى أَرْضِ الْعَدُوِّ مَخَافَةَ أَنْ يَنَالَهُ الْعَدُوُّ