“As a scientist, Moses rises above all other Biblical characters because of his stupendous knowledge of public health and hygiene. The safe-guarding of the people Israel under the difficulties encountered should, perhaps, rank as the greatest achievement in all medical history.” (Modern Science and Christian Faith, 2^nd ed; Wheaton, IL: Van Kampen Press, 1950), p. 238. 

Dr. Vis uses leprosy as an example of Moses’ unique insight into prevention and the spread of disease that wasn’t known to modern science until fairly recently. The word “quarantine” originated in the fourteenth century when the Italian ports of Venice and Genoa first refused admission to immigrants who might be harboring bubonic plague and required them to stay on board for forty days (hence “quarantine”). But Moses and Israel were practicing it centuries earlier.

Moses disinfected clothing (Lev 13:47), beds, and even houses (Lev 14:34). The leper was required to wear a covering (mask) over the upper lip (Lev 13:45). Priests often had to go “outside” the camp to examine the sick, further protecting the general population (Lev 13:46). Some of these purification techniques involved rinsing or burning the garment of a diseased person, shaving the head and/or eyebrows (Lev 14:8-9) and sterilization by means of fire (Lev 13:55-58). The idea of “germs” as we know them causing disease was, as far as we know, unknown in Moses’ day – yet there was an awareness in the nation of the importance of cleanliness and hygiene. 

Some other interesting prohibitions include the refusal to eat any animal which had died a natural death (Lev 7:24). Excreta was to be buried or burned (Deut 23:12-14; Ex 29:14/it wasn’t until World War I that these precautions were implemented). Containers made of porous materials that could never be sufficiently cleaned and reused were to be broken and destroyed (Lev 11:33). It is important to start with clean water (Lev 11:32-38). The use of running water is better than standing water for cleaning (Lev 15:13/a.k.a. rinsing dishes, showers are better than baths, etc.). Any food container not sealed with a tight lid was considered unclean (Num 19:15/the beginning of TupperwareJ?). 

Did Moses learn this stuff while he was in Egypt? Dr. M. R. DeHaan, who received his M.D. from the University of Illinois Medical School and practiced medicine for many years before becoming a preacher of the Gospel believes not. He says, “Although [Moses] deals in detail and great length with diseases, the treatment of infections, leprosy, and running sores, yet the illusions, deceptions, gross errors, and superstitions concerning anatomy, physiology, pathology, and treatment of diseases as taught in the highest schools of learning in Egypt from which Moses was a graduate (Acts 7:22), are never taught or even suggested in the books of Moses. But instead the instructions Moses laid down for Israel were utterly at variance with the accepted practices of that day, and fully in harmony with modern-day scientific facts.” M.R. DeHaan, M.D., Genesis and Evolution (Grand Rapids, MI: Zondervan, 1962), p. 61.

It is my personal opinion that God taught Moses these things while they were together on Mount Sinai along with the giving of the Law and an explanation of early world history (creation, etc.).