Whose religious freedom?

Michele Chabin reports that Israeli postal workers are refusing to deliver Hebrew-language New Testaments. Mark Silk asks an interesting question:

Let's suppose that thousands of American postal workers similarly refuse
to deliver English copies of the Koran mailed by a Muslim organization
to hundreds of thousands of American households in hopes of making
converts. Whose religious liberty rights should prevail--the senders of
the material exercising their own Islamic Great Commission? Or the
postal workers who contend that participating in such an exercise would
violate their religious beliefs?