Various aspects of ʿilm al-ḥurūf or science of letters has become subjects of recent scholarly works, which have increasingly identified it as lettrism, a major subset of Islamic occult sciences (e.g., Melvin-Koushki 2016, 2019; Gardiner 2021; Saif 2017). Matthew Melvin-Koushki defines lettrism as a method “centered on letters as keys to deciphering (and manipulating) all levels of physical, imaginal and spiritual reality” (2014, 250). Lettrism as a whole, thus, seeks to read cosmological letters, words, and signs, and decipher the world as a book of God. It is not an overstatement to say that lettrism would become the most “Islamic” of all occult sciences as its premises would be readily justifiable with various Qurʾanic verses. Focusing on the work of the 13th-century Muslim mystic, ʿAzīz al-Dīn Nasafī, I examine how Qurʾan and lettrism intersect and cross-fertilize one another, which provides unbeatable authority for lettrism as a science that is rooted in the sacred scripture. Nasafī has been largely absent from ongoing conversations on Islamicate occult sciences. I argue that he extensively draws on two Qurʾanic terms, the tablet (lawḥ) and the pen (qalam) (e.g., 68:1), to demonstrate that the world in its entirety is a book of God. Earlier Muslim philosophers and thinkers had often argued that the pen and the tablet refer to the First Intellect (ʿaql al-awwal) and the Universal Soul (nafs al-kullī). Nasafī also incorporates them in his cosmology. However, he offers a series of arguments to prove that these terms cannot be restrained to these two ontological realities. He argues that these terms are best understood as universal apparatuses that constantly write the world from above to below. In this sense, the pen and the tablet are applicable to various cosmological planes and the hierarchy of being, and they identify the universal writing of God across the universe.