And whosoever toucheth his bed
 Is unclean. According to the Misnah F24, a bed defiles a man seven ways, so as to defile garments; standing, sitting, lying, hanging, and leaning, and by touching, and by bearing: 
 shall wash his clothes, and bathe [himself] in water;
 in forty seahs of water, as the Targum of Jonathan: 
 and be unclean until the even;
 be unfit for conversation with other men till the even, though both his body and clothes are washed.