The Mekhilta, the tannaitic midrash on Exodus, probes the geographic scope of the tenth plague with meticulous care. The verse states: "And the Lord smote every firstborn in the land of Egypt" (Exodus 12:29). The phrase "in the land of Egypt" seems straightforward, but the rabbis ask — what about firstborn Egyptians who happened to be somewhere else? And what about firstborn from other nations who happened to be in Egypt?
The Mekhilta answers both questions using additional verses from Psalms. First, regarding Egyptian firstborn who were abroad: (Psalms 136:10) says "Who smote Egypt by their firstborn" — meaning the plague followed Egyptian firstborn wherever they were, not only within Egypt's borders. If an Egyptian firstborn was visiting another country that night, he died there.
Second, regarding the firstborn of other nations — specifically the descendants of Ham, including Cush, Put, and Lud — the Mekhilta cites (Psalms 78:51): "He smote every firstborn in Egypt, the first-fruit of their strength in the tents of Ham." The plague struck the firstborn of all the Hamite peoples, not only the Egyptians proper.
The scope of the tenth plague was therefore far wider than a casual reading suggests. It was not limited to one country's borders. It targeted a lineage — the house of Ham — and it pursued that lineage across every geography. <strong>God's</strong> judgment on the night of Passover recognized no boundaries.