Leviticus 15:19

She shall be put apart Not out of the camp, but from converse with her husband and others, and from access to the house of God. Seven days During the time of her infirmity, which might perhaps continue so long, and it was decent to allow time for her purification after the ceasing of her issue. Whosoever toucheth her Of grown persons; for the infant, to whom in that case she might give suck, was exempted from this pollution by the greater law of necessity, and by that antecedent law, which required women to give suck to their own children.