The absorbent, tough, elastic skeleton of certain aquatic animals found in abundance in the waters of the eastern Mediterranean Sea and elsewhere. Sponges were probably obtained (in the past as today) by divers who removed them by hand from underwater rocks. After the living animal died and decayed within its skeleton, the sponge was washed thoroughly until only the skeleton remained.

The sponge’s ability to absorb and release liquids made it commercially important in ancient times. While Jesus Christ was on the torture stake he was offered some sour wine contained in a sponge that was at the end of a reed.​—Mt 27:48; Mr 15:36; Joh 19:29.