Chabad.org — English translation + Rashi
Torah Temimah points to Zevachim 93b.
E-Daf.com — Zevachim 93b
HebrewBooks / Shas PDF
English: “His finger” — his own finger, and not the finger of another.
Own finger required — the kohen must dip his own finger; the finger of another is invalid.
The kohen must dip his own finger; the finger of another is invalid. The verse’s language “his finger” restricts the act of tevilah to the performing kohen’s own digit. Use of another person’s finger fails the requirement and cannot serve for the subsequent applications of blood.