The letters of Imam Ali (AS), the Commander of the Faithful, addressed to rulers, scholars, and people of various lands, represent a vital intellectual treasure within Islamic hadith and historical heritage. The detailed covenant letter to Muhammad ibn Abi Bakr, following that of Malik al-Ashtar—and in some respects surpassing it—is deemed the most significant, comprehensive, and elaborate letter issued by Imam Ali (AS). Its distinction from other letters to Muhammad lies in the ambiguity of its textual boundaries in sources, potentially challenging its authenticity in attribution and content. Thus, an independent study on the genealogy of this covenant letter was necessary, employing a library-based method for data collection and a descriptive-analytical-comparative approach for processing, aiming to refine and analyze its content. The study addresses: How many letters did Imam Ali (AS) write to Muhammad ibn Abi Bakr, and which sources have reported them? How is the covenant letter reflected in hadith and historical sources? How is its authenticity evaluated? Findings revealed seven letters reported in fifteen early sources, with the detailed covenant letter appearing in the eighth, varying in elaboration, segmentation, and combination of passages. Its authenticity is readily proven through reliable verification methods supported by corroborative evidence.