This study aims at identifying the main aspects of the textual coherence in Sibawaih's book. It attempts to follow the footsteps of the earliest analyses of the book with a new textual vision. It tries to answer three important questions that crosse one's mind whenever the book is being read. First, why is this book mysteriously resisting to all kinds of change and modification? Second, what is the secret that makes this book over lasting and challenging the current textual studies? Third, how can the linguistic law, including the speaker, the receiver, and the context make this book a reference in the field of textual studies? The questioning triangulation in this paper serves as a framework for the present study as far as textual analysis is concerned. It also tried to draft its major principles according to Sibawaih's grammatical discourse. The findings of this study revealed that most of the textual principles are the result of reviewing and analysing Sibawaih's grammatical discourse. These principles represent functional grammar pragma-linguistics, and socio-pragmatics, including coherence, cohesion, deletion as well as cataphoric and anaphoric variations