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Numbers 8:7
Brenton's English Septuagint · Berean Standard Bible
And thus shalt thou perform their purification: thou shalt sprinkle them with water of purification, and a razor shall come upon the whole of their body, and they shall wash their garments, and shall be clean.
This is what you must do to cleanse them: Sprinkle them with the water of purification. Have them shave their whole bodies and wash their clothes, and so purify themselves.