He—may Allah Most High have mercy on him—was also asked:

A tailor sewed a silk strap bearing a gold cross for Christians. Does he incur sin by sewing it? Is his payment lawful or not?

He replied:

Yes. If a man assists in disobedience to Allah, he incurs sin because he has cooperated in sin and transgression. For this reason, the Prophet, peace and blessings be upon him, cursed wine, the one who presses it, the one for whom it is pressed, the one who carries it, the one to whom it is carried, its seller, its buyer, the one who serves it, the one who drinks it, and the one who consumes its proceeds. Most of these people—such as the one who presses it, carries it, or serves it—merely assist in its consumption.

For this reason, selling weapons to someone who will use them in unlawful fighting, such as fighting Muslims or fighting during civil strife, is forbidden. If this applies to assisting in sins, then how much more so to assisting in unbelief and its religious observances!

It is not permissible to make a cross, whether for payment or without payment, nor to sell it as a cross, just as it is not permissible to sell or make idols.

As recorded in the authentic collection, the Prophet, peace and blessings be upon him, said:

“Indeed, Allah has forbidden the sale of wine, carrion, swine