In ancient times the term pestilence referred not only to infectious disease caused by Yersinia pestis, but also to several different epidemics. We explore the relations between references in the Bible and recent scientific evidence concerning some infectious diseases, especially the so-called Plague of the Philistines and leprosy. In addition, some considerations regarding possible connections among likely infectious epidemic diseases and the Ten Plagues of Egypt are reported. Evidence suggesting the presence of the rat in the Nile Valley in the II millennium BC is shown; a possible role of the rat in the plague spreading already in this historical period should be confirmed by these data. While the biblical tale in the Book of Samuel may well report an epidemic event resembling the plague, as to date this infectious disease remains unknown, it is not conceivable to confirm the presence of leprosy in the same age, because the little palaeopathologic evidence of the latter disease, in the geographic area corresponding to Egypt and Palestine, is late, dating back only to the II century AD.