Numbers 31:24
Ye shall also wash your clothes on the seventh day, and ye shall be clean, and afterwards ye shall come into the camp.
Leviticus 11:25
And whoever bears any part of their carcase shall wash his clothes and be unclean until the evening.
Leviticus 14:9
But it shall be that on the seventh day he shall shave all his hair off his head and his beard and his eyebrows; finally he shall shave off all his hair, and he shall wash his clothes; also he shall wash his flesh in water, and he shall be clean.
Leviticus 15:13
And when the one that has an issue is cleansed of his issue; then he shall number to himself seven days from his purification and wash his clothes and bathe his flesh in living water, and he shall be clean.
Numbers 19:19
And the clean person shall sprinkle upon the unclean on the third day and on the seventh day; and when he has removed the sin from them the seventh day, he shall then wash his clothes and bathe himself in water and shall be clean in the evening.