Numbers 31:24
And you shall wash your clothes on the seventh day, and you shall be clean, and afterwards you shall come into the camp.
Leviticus 11:25
And whoever carries the carcass of them shall wash his clothes and be unclean until the evening;
Leviticus 14:9
But on the seventh day he shall shave all his hair off his head and his beard and his eye-brows; even all his hair shall he shave off. And he shall wash his clothes. He also shall wash his flesh in water, and he shall be clean.
Leviticus 15:13
And when he who issues is cleansed of his issue, then he shall number seven days to himself for his cleansing, and wash his clothes, and bathe his flesh in running water, and shall be clean.
Numbers 19:19
And the clean person shall sprinkle on the unclean on the third day, and on the seventh day. And on the seventh day he shall purify himself, and wash his clothes, and bathe himself in water. And he shall be clean at evening.