Persian Letters uses both the Bible and the Qur’an as powerful symbols not just of religious faith but of the strict and proscriptive rules and practices that inform its outward structure. The holy books of the Jews and Zoroastrians are also invoked in proving that religious texts contain the ideas of ordinary people that symbolically stand in for words of God. In this way, Montesquieu achieves a double symbolic value of the sacred scriptures.

Montesquieu references to holy books in a variety of tones and moods, from contemplative and serious to ironic and even comedic. In this manner, he satirizes numerous systems of superstition and magical thought. Furthermore, the religious leaders often invoke holy books when they want to threaten, persuade, convince, or belittle, and in those instances the scriptures become symbols of power, especially the absolutist power of the ruler. Montesquieu shows that holy books can become symbols of desperate defense against change when Rica mistakenly attaches the significance of the Qur’an to the papal bull.

Persian Letters is one of the first novels where foreignness/otherness is used as a two-pronged, often distressingly ambiguous symbol of alienating “monstrosity” (used in a metaphorical sense of unaccepted and scary non-belonging) and welcomed observational objectivity.