Why are the biblical references to Mary considered too limited for a complete biography?

Biblical references to Mary are considered too sparse to construct a complete or integrated biography because they provide only fragmented glimpses of her life rather than a continuous narrative.12

While Mary appears in several key Gospel incidents—such as the Annunciation, the birth of Jesus, the Passover visit to Jerusalem, and the station at the cross—these scenes do not form a cohesive portrait. Her role is significant primarily within the narratives of the Nativity and the Passion, but the texts often leave her motivations and personal history unaddressed. For instance, the Gospels do not specify her age, the length of her engagement to Joseph, or details regarding her childhood.134

Because the canonical scriptures lack these biographical details, later traditions—such as the noncanonical Protevangelium of James—were developed to fill these gaps and enhance her role in Christian tradition. Consequently, much of what is known about Mary beyond these brief biblical mentions is the result of centuries of theological development and contemplation.412