In Islam we are free to wear anything so long it does not fall into one of the following categories:
1. It should not be transparent, revealing the parts of body that ought to be covered.
2. It should not considered as specifically worn by the opposite sex.
3. It should not be specifically a religious symbol of another religion or ideology.So, the wearing of a symbol of a religion other than Islam is not permissible.
Here is the fatwa issued by the late Sheikh Ibn `Uthaymeen, a prominent Saudi Muslim scholar, that reads:
“There is no way to deem it permissible to wear clothes that contain the cross. A Muslim is never permitted to wear it because this is considered an act of propagating the religion of other people and the representation of a creed that violates the Qur’an and the bases of Islam.
Having stated the above, it becomes clear that a Muslim is not permitted to wear such clothes that contain any symbols like the cross or the Jewish star. A Muslim should avoid any symbols that violate the pure and clean `aqeedah (creed) of Islam.