Leviticus 15:22
And whosoever toucheth any thing that she sat upon shall wash his clothes, and bathe himself in water, and be unclean until the even. And whosoever toucheth any thing that she sat upon shall wash his clothes, and bathe himself in water, and be unclean until the even.
Anyone who touched anything on which she had sat was to wash his clothes and bathe himself in water and remain unclean until the evening. It stands within the laws regulating uncleanness and cleansing in Leviticus 12-15, and those chapters stand within the Levitical laws and services of Leviticus 1-16 that formed part of the yearly sanctuary service typifying Christ's ministry. It stands with the Leviticus 15-17 portion of the larger section of Leviticus 5-23 dealing largely with laws relating to sacrifices and offerings, the consecration and duties of the priests, and the various feasts of the year.
It belongs to laws of personal purity similar to customs practiced by the Zulus. The period of uncleanness meant isolation from other people for the rest of the day, allowing air and sunshine to complete disinfection, and these simple rules of cleanliness and isolation were intended to prevent disease from spreading. This shows that while God declares Himself the God who heals, He demands proper precaution on the part of His people.
These bodily impurities had to be visibly removed before the sanctuary's real cleansing by blood, distinguishing that preliminary physical cleansing from the moral defilement of the sanctuary. Like each detail in these laws, the verse has a fuller meaning found in the sacrifice, life, and work of Jesus Christ, for all the sacrifices are types and all the slain beasts point forward to the Lamb of God that takes away the sin of the world. The dry details gain new life and become a blessing only when read remembering this.
The uncleanness laws are mighty object-lessons emphasizing how sinful sin is everywhere and showing the exceeding sinfulness of sin, with the chapter's laws concerning uncleanness and leprosy presenting leprosy as a fitting type of sin. The cleansing laws given to ancient Israel serve as an example of cleansing truths that Christians should not abandon: obedience to health principles helps prepare the body, God's temple, to receive the Holy Spirit and become a clean vessel for the latter rain.