Charles Ellicott Commentary Jeremiah 13:23

"Can the Ethiopian change his skin, or the leopard his spots? then may ye also do good, that are accustomed to do evil." — Jeremiah 13:23 (ASV)

Can the Ethiopian ...? —Literally, the Cushite. The meaning of the question is obvious. The evil of Judah was too deep-ingrained to be capable of spontaneous reformation. There remained nothing but the sharp discipline of the exile. The invasion of Tirhakah and Pharaoh-nechoh, the presence of Ethiopians among the servants of the royal household (Jeremiah 38:10), the interaction with the upper valley of the Nile implied in Zephaniah 3:10, Psalms 68:31, and Psalm 87:4, had made the dark-skinned people from Africa familiar figures.

Possibly the use of leopard-skins by Ethiopian princes and warriors, as seen on Egyptian monuments and described by Herodotus (vii. 69), had associated the two thoughts together in the prophet’s mind. If the king’s household were present , he may have pointed to such a one, Ebedmelech (Jeremiah 38:10), or another similarly arrayed, to illustrate his words.