Philistines stole Israel’s most sacred object, the Ark of the Covenant, which held the Ten Commandments. Then sent it on tour as a war trophy. “A plague of tumors” broke out everywhere it went. Philistines sent it back to the Jews, with an offering: a chest of gold rats and gold lumps that looked like tumors. Scholars speculate that the disease may have been the rat-carried bubonic plague, with produces tumors on the skin. Complete Guide to the Bible, p. 89.