In sum, it is impermissible for a Muslim to lend assistance to the people of falsehood or to hire himself out in places of associationism and idolatry—such as churches, tomb-shrines, and other venues of the unbelievers and polytheists—for by doing so he helps them in their falsehood and tacitly approves their evil. Any income he earns thereby is unlawful, and we seek refuge in Allah.
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Tardiness in performing one’s job

Question: I work for the postal service. My scheduled hours are from 9:00 a.m. to 1:00 p.m., and from 5:30 p.m. to 6:30 p.m. Because my home is far from the office and I have other work in the evening, I am unable to attend during the evening hour; therefore I do not go to the office at that time. My immediate supervisor is aware of this, yet I do not know whether he is content with my absence or not. Is it permissible for me to do this while still taking my full salary? Kindly advise me—may Allah reward you.

Answer: It is well known that an employee who is hired to perform a specific task is obligated to carry it out fully and faithfully, and he is entitled to his wage only upon completing the work for which he was hired.

What the questioner describes—delaying the performance of his duties and forfeiting part of the work hours for his own private matters—is not permitted. The portion of his salary that he receives for the time in which he did not work is unlawful; it is illicit earnings because he has taken it without right. Even if his immediate supervisor or manager were to overlook the matter, so long as the general regulations do not allow such absenteeism, this does not make his tardiness permissible. The time in question has already been contractually allocated to the job, and he may not be absent from it without a valid sharʿī excuse that would lawfully permit such an absence.