Praise be to Allah Lord of the worlds, and may Allah’s peace and blessings be upon our Prophet Muhammad, his family and all his companions.
Wa `Alaikum Assalam wa Rahmatullahi wa Barakatuh.
As to what follows:
What is obligatory is to safeguard the Qur’an from the hands of the disbelievers, except for an apparent benefit. However, if the mus'haf ends up in the hands of those who are not permissible to have it without involvement of a Muslim, like a kafir purchasing it, or taking it from someone who gives it to them, then there is no sin on he who is not a cause in it.
Finally, we would like to point out that the Shariah term [for Christians] is 'Nasara' (and not 'Masihiy'), as Allah named them in the Qur’an.
Khalid bin `Abdullah al-Muslih
9 / 11 / 1428 AH