God’s Laws of Health.
The biblical laws of sanitation were clearly ahead of their time! There was really no way to fully understand the reasons for these laws until the invention of the microscope, the discovery of bacteria and the pioneering work of pathologists in recent centuries, yet these ancient biblical laws have proven scientifically valid today!
People who touched a dead or diseased animal or person—or even garments or secretions from a sick person—were to bathe and wash their clothes and avoid contact with others. Contaminated garments were to be washed or burned—important sanitizing principles that are still followed today. Dwellings that showed signs of mold, or that had harbored sick individuals, were to be cleaned, repaired or destroyed, to prevent the spread of disease (see Leviticus 13–15).
Porous vessels that came into contact with dead animals were to be broken, since they would harbor bacteria. People showing signs of sickness were to be isolated—quarantined—until examined by a priest and declared well. People were to wash after having sex. Tattoos and cuttings on the flesh were also forbidden (Leviticus 19:28), for reasons that include the risk of contracting disease. Modern physicians warn that tattoos and body-piercing carry a risk for contracting infectious diseases like hepatitis B, hepatitis C, syphilis and HIV/AIDS (International Journal of Infectious Disease, 2001, 5(1), 27–34). 
In Deuteronomy 23:9–14, we learn that human wastes were to be buried, away from human dwellings. Today we call this sanitary waste disposal, and its benefits are widely understood but not always practiced—especially in poverty-stricken areas. History is filled with epidemics of typhus, cholera and dysentery, linked to the careless dumping of human waste into streets and rivers, or feeding human waste to animals that are then eaten. Burying human waste breaks the life cycle of many parasitic organisms that spread disease. This simple practice is much more effective, and less expensive, than treating disease after it breaks out—and God put this principle in the Bible thousands of years before mankind’s science understood its benefit!