The Reception Architecture of 666: A Computational Case Study of Hermeneutic Drift in Revelation 13:18

This paper applies the Structural Hermeneutic Drift (SHD) framework introduced in \citet{abella2026shd} to the reception trajectory of the numerical marker \emph{666}, from its appearance as a fiscal-imperial metric in 1 Kings 10:14 (c.~950 BCE) to its doctrinal condensation in Augustine's \emph{De Civitate Dei} XX (c.~426 CE). The case is treated as a single deep-validation study complementary to the breadth-cohort validation of Paper 1, with empirical analysis performed across Hebrew, Greek, and Latin textual layers and across eight patristic agents. The corpus analysis combines closed-vocabulary semantic field coding, cross-lingual Drift Index measurement, dynamic polarity decomposition across the eleven blocks of Revelation, and gematric robustness testing under five numerological systems. The findings comprise five primary empirical results. First, the semantic field surrounding \emph{666} undergoes a measurable cross-lingual inversion at the testamentary boundary: the fiscal-to-demonological token ratio shifts from 32.0 (1 Kings 9--11) to 0.27 (Revelation), with the same inversion preserved across all three linguistic layers analyzed. Second, the adversarial field of Revelation is already saturated before the marker is introduced (129 Beast-aligned tokens distributed across the five pre-marker blocks), supporting a re-classification of the marker as an internal condensation node within an established architecture rather than as the originating Friction event of that architecture. Third, the Mass-Function-Efficiency decomposition shows that the marker block (Revelation 13:18) occupies a uniquely extremal configuration in the three-dimensional MFE space, consistent with its role as a maximally citatable, recognizable, and replicable transmission handle. Fourth, the patristic stabilization curve across eight agents documents the Fiscal Index collapse (64\% to 0\%), the Demonological Index stabilization (0\% to 44\%), and a spike in the Antichrist Coupling at Irenaeus (19\%), with the computed installation window $\Delta T_{\text{install}} = 84$ years from Friction (c.~96 CE) to Stabilization (c.~180 CE). Fifth, the gematric value 666 lies outside the top-50 most frequent values in the Hebrew biblical corpus under three numerological systems, supporting an interpretation of the marker as a deliberately constructed symbolic identification rather than a coincidental lexical density product. Three negative controls (the sacred numbers \emph{7}, \emph{12}, \emph{40}) exhibit high lexical drift across the testamentary boundary but null structural drift under the SHD criteria, confirming the framework's discriminative resolution between vocabulary variation and frame replacement. The analysis identifies five candidate methodological refinements to the SHD framework---the constitutive-vs-condensation distinction, the MFE extremal-configuration hypothesis, a refined fast-installation pattern, a compound robustness-plus-rarity criterion for gematric authentication, and a terminological distinction between Lexical and Field Drift Indices---each presented as a candidate refinement requiring validation against additional cases. The paper is offered as a paradigmatic deep-case study within the SHD research program, not as a theological intervention or a closure of the active scholarly debate over the referent of \emph{666}.