Reflecting on that, didn't Prophet Yusuf (Joseph) work as a wealth secretary or minister for the Egyptian king who was non muslim?
And the king said, "Bring him to me; I will appoint him exclusively for myself." And when he spoke to him, he said, "Indeed, you are today established [in position] and trusted."
[Yusuf (Joseph)] said: "Set me over the storehouses of the land; I will indeed guard them with full knowledge"
Thus did We give full authority to Yusuf (Joseph) in the land, to take possession therein, as when or where he likes. We bestow of Our Mercy on whom We please, and We make not to be lost the reward of Al-Muhsinun (the good doers)
[Qur'an [Surah Yusuf] 12: 54-6]
http://quranicrealm.com/quran.php?q=12
Allah knows best.
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