Leviticus 15:4

Every bed whereon he lieth that hath the issue is unclean,.... Which he constantly makes use of; so the Targum of Jonathan, which is peculiar to him, and appointed and appropriated for him to lie upon. Jarchi says, every bed that is fit to lie upon, thou is appropriated to another service; but, he adds meaning is, which he shall lie upon (or continue to lie upon); for it is not said, which he hath laid upon, but which he lieth upon, and is used by him continually; according to the Misnah u, a man that has an issue defiles a bed five ways, so as to defile a man, and to defile garments; standing, sitting, lying, hanging, and leaning:

and everything whereon he sitteth shall be unclean; which is appropriated to sit upon; and so the Targum, as before, what is his proper peculiar seat, what he is used to sit upon, and is fit for that purpose: and it is observed by some Jewish writers w that a vessel that is not fit to sit upon is excluded, as if a man was to turn up a bushel, or any other measure, to sit upon it; see Titus 1:15.

u Zabim, c. 2. sect. 4. w Maimon. Bartenora in Misn. Niddah, c. 6. sect. 3.