Chabad.org — English translation + Rashi
Torah Temimah points to Zevachim 93b.
E-Daf.com — Zevachim 93b
HebrewBooks / Shas PDF
English: Seven times — and not six, and not eight.
Exact count of seven — the blood must be sprinkled exactly seven times before the parochet.
The blood must be sprinkled exactly seven times before the parochet. The Torah’s specification of “seven times” is taken as a precise requirement. Performing six or eight applications fails to fulfill the mandated count and renders the service incomplete for the High Priest’s chatas.