Although a textual relationship between Arabic Muslim texts and their rendition through Swahili epic poems (tendi) is acknowledged in Swahili poetry studies, “translation” is not a straightforward explanation of this relationship. Furthermore, Swahili narrative poems on the prophets (manabii), mostly created at the end of the 19th century, have seldom been considered in textual relation to the Qiṣaṣ al-Anbiyā’ literature or to the Qur’ān. Thus, important questions have not been asked: How did the Arabic stories of the prophets arrive on the Swahili coast? How did poets appropriate these stories and forge them into a new narrative discourse? In this paper, I focus on tafsiri as a form of appropriation and adaptation, applying Gérard Genette’s concept of “palimpsest” to analyse the textual relationship between Arabic Muslim and Swahili literary texts. This will allow me, through a close reading of these texts and consideration of both language and genre, to identify the palimpsestuous presence or rather copresence of Arabic source texts within Swahili works. Ultimately, this method offers a model for future philologies of world literature.