Leviticus 8:35

35At the entrance of the tent of meeting you shall remain day and night for seven days, performing what the Lord has acharged, so that you do not die, for so I have been commanded.”

Ezekiel 43:26-27

26Seven days shall they make atonement for the altar and cleanse it, and so consecrate it.
Hebrew fill its hand
27And when they have completed these days, then cfrom the eighth day onward the priests shall offer on the altar your burnt offerings and your dpeace offerings, and eI will accept you, declares the Lord God.”

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