Leviticus 13:53-59

“And if the priest examines, and if the disease has not spread in the garment, in the warp or the woof or in any article made of skin, then the priest shall command that they wash the thing in which is the disease, and he shall shut it up for another seven days. And the priest shall examine the diseased thing after it has been washed. And if the appearance of the diseased area has not changed, though the disease has not spread, it is unclean. You shall burn it in the fire, whether the rot is on the back or on the front. “But if the priest examines, and if the diseased area has faded after it has been washed, he shall tear it out of the garment or the skin or the warp or the woof. Then if it appears again in the garment, in the warp or the woof, or in any article made of skin, it is spreading. You shall burn with fire whatever has the disease. But the garment, or the warp or the woof, or any article made of skin from which the disease departs when you have washed it, shall then be washed a second time, and be clean.” This is the law for a case of leprous disease in a garment of wool or linen, either in the warp or the woof, or in any article made of skin, to determine whether it is clean or unclean.