This presentation aims to conceptualize the engagement of fifteenth-century vernacular texts with the debates of knowledge/science (ʿilm) and gnosis (maʿrifa). The fifteenth-century Ottoman vernacular intellectuals did not follow passive authorial practices while compiling their texts in various genres through the information gathered from Arabic and Persian Sources. Their reconfiguration of knowledge in their compilations denotes the original part of their scholarly contributions. This presentation starts off from the debates about the esoteric interpretation of a specific Quranic verse: “I did not create jinn and humans except to worship (yaʿbudūn) me” (Quran 51:56). Sufi commentators usually construed yaʿbudūn (worship/serve) as yaʿrifūn (know/recognize). However, the fifteenth-century Ottoman vernacular intellectuals that this presentation investigates rejected the aforementioned construal in an attempt of transmitting knowledge for Turkish-speaking reading communities. In this presentation, I examine guidebooks such as Manyasoğlu’s (d. after 1438) ʿAcebü’l-ʿÜccāb, the several books of The Wonders of Creation, Ahmed-i Dāʿī’s (d. after 1421) miscellaneous pieces, along with the books of creed (ʿaqāʾid) and catechism (ʿilm al-ḥāl). I argue that in terms of attaining the truth or practicing sciences, vernacular intellectuals such as Manyasoğlu and Dāʿī attempted to “exotericize” the mystical sciences, and rejected the idea of gnosis, whereas other Sufi-minded authors underscored the esoteric aspects of the truth; hence vernacular texts represent a spectrum of dialogue, challenge and refutation within the larger context of Islamicate intellectual activities.