Autosacrifice (Ritual Bloodletting)

Human sacrifice draws most modern attention to Aztec religion, but autosacrifice was the far more common and far more personal form blood offering took, performed routinely rather than reserved for a rare ceremony. The Florentine Codex, compiled under Bernardino de Sahagun with Nahua informants after the conquest, describes priests drawing blood from their own ears, legs and other parts of the body multiple times a day as a basic devotional discipline, and depicts commoners doing the same at household shrines, at the dedication of a new building, on a child's naming day and before major undertakings such as a journey or a marriage.

Maguey spines, from the same agave plant that supplied fiber, food and the fermented drink pulque, were the everyday instrument, while spines from stingrays traded up from the Gulf and Pacific coasts carried higher ritual prestige and were reserved for more significant occasions and higher status practitioners, including rulers depicted piercing their own tongues or ears in codex illustrations of royal accession and temple dedication ceremonies. Archaeologists have recovered bloodstained paper offerings and spine fragments from household shrine deposits as well as temple precincts, physical evidence that the practice reached well beyond the priesthood into everyday domestic devotion across Aztec society.

Scholars of Aztec religion read autosacrifice and human sacrifice as related but conceptually distinct within the same debt theology. Autosacrifice was blood a person gave from their own body, voluntarily and repeatedly, matching in kind, if not in scale, the self inflicted wounds the gods gave themselves at Teotihuacan to start the sun moving. Human sacrifice, most often of war captives, was blood taken rather than given, and Mexica sources frame the captured warrior's death differently again, sometimes as an honored continuation of his own martial identity rather than a simple extraction, a distinction anthropologists and historians such as David Carrasco have worked to keep visible against flatter popular readings that treat all Aztec bloodletting as a single undifferentiated practice of violence.

Blood offered from one's own body carried an immediacy human sacrifice could not, since it needed no captive, no war and no priestly apparatus beyond a spine and a strip of paper, and its sheer frequency in the archaeological and textual record, evidenced by bloodstained paper offerings recovered from Aztec sites and by the codices' repeated depiction of the act, argues that autosacrifice, not the more famous mass sacrifice, was the daily texture of Aztec religious devotion for most people who practiced it.