A Biblical First
The phrase “two-edged sword” first entered the English language in William Tyndale’s 1525 translation of the New Testament Letter to the Hebrews: “For the word of God is quick, and mighty in operation, and sharper than any two-edged sword” (Hebrews 4:12). Though the term originally referred only to an extremely sharp weapon or a blade that could cut in either direction, it has become a common metaphor (along with the related “double-edged sword”) to describe an idea that can be dangerous in either outcome or direction.
Source: Stanley Malless and Jeffrey McQuain, Coined by God, New York: W.W. Norton, 2003.
MLA Citation
“A Biblical First,” Biblical Archaeology Review 32.5 (2006): 18.