Seven days before circumcision, then the eighth
December 25–31 + January 1 · 7 + 1 = 8 counted dates.
7 dates before circumcision + 1 covenant day = 8
December 26–31
December 25 → January 1
December 25 through January 1
Full supporting table · File 13 §7.1 · File 69 §3.4C · Luke 2:21, BSB
Counting and source notes
The terminal exclusion is explicit: the first seven-date block includes the birth date and excludes January 1. It is not a claim that seven full days had elapsed at the December 31 marker. The whole December 25–January 1 sequence is eight dates inclusively, separated by seven elapsed days. The traditional calendar supplies the dates; Luke supplies the circumcision and naming sequence. In the separate day-year table December 31 is coordinate 0, displayed symbolically as 1 BC.
Image version and downloads for Figure 3

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