47 “When a garment has a [af]mark of leprosy in it, whether it is a wool garment or a linen garment, 48 whether in [ag]warp or woof, of linen or of wool, whether in leather or in any article made of leather, 49 if the mark is greenish or reddish in the garment or in the leather, or in the [ah]warp or in the woof, or in any article of leather, it is a leprous mark and shall be shown to the priest. 50 Then the priest shall look at the mark and shall [ai]quarantine the article with the mark for seven days. 51 He shall then look at the mark on the seventh day; if the mark has spread in the garment, whether in the warp or in the woof, or in the leather, whatever the purpose for which the leather is used, the mark is a [aj]leprous malignancy, it is unclean. 52 So he shall burn the garment, whether the warp or the woof, in wool or in linen, or any article of leather in which the mark occurs, for it is a [ak]leprous malignancy; it shall be burned in the fire.
53 “But if the priest shall look, and indeed the mark has not spread in the garment, either in the warp or in the woof, or in any article of leather, 54 then the priest shall order them to wash the thing in which the mark occurs and he shall [al]quarantine it for seven more days. 55 After the article with the mark has been washed, the priest shall again look, and if the mark has not changed its appearance, even though the mark has not spread, it is unclean; you shall burn it in the fire, whether an eating away has produced bareness on the top or on the front of it.
56 “Then if the priest looks, and if the mark has faded after it has been washed, then he shall tear it out of the garment or out of the leather, whether from the warp or from the woof; 57 and if it appears again in the garment, whether in the warp or in the woof, or in any article of leather, it is an outbreak; the article with the mark shall be burned in the fire. 58 The garment, whether the warp or the woof, or any article of leather from which the mark has departed when you washed it, it shall then be washed a second time and will be clean.”
59 This is the law for the mark of leprosy in a garment of wool or linen, whether in the warp or in the woof, or in any article of leather, for pronouncing it clean or unclean.
Here we have more practical guidance on dealing with contagions like leprosy. God cared very much about their health and safety, and didn’t want anything “unknown” to harm them. So he gave them instructions on taking care of diseased garments. They didn’t have washing machines, so I suspect nasty bugs/bacteria very much liked to hang out in clothes that hadn’t been taken care of well. We can be thankful that we know much more about disease, and indeed, about general sanitation, and have the convenience of washing machines, however tedious it might be to do the laundry. So thank God for washing machines (and a thousand other modern conveniences).