Proverbs 27:17, “Iron sharpens iron, and one man sharpens the face his neighbor,” is almost universally seen as positive. Some view this maxim as an example of “tough love,” others as a rewording of a verse earlier in this passage, “Faithful are the wounds of a friend” (27:6). There is little evidence, however, for these interpretations, which appear to reflect modern connotations of “sharpness.” In fact, the biblical evidence for parts of a face that are “sharp” suggests a more negative reading, for sharp eyes or a sharp tongue show an intent to do violence or bring about destruction. The usage of the LXX’s verb for “sharpen” (παροξύνω) elsewhere confirms this interpretation. Proverbs 27:17 may therefore be stating that, just as an iron hammer violently pounds out soft iron in the smithing process, so too may a same-gender neighbor engage in a similarly violent act, in a manner that is little different from that of a contentious wife. This study of the Hebrew and Greek verbs for “sharpen” suggests that v. 17 continues the idea of “friendships” to be avoided (vv. 13–16). The previous passage, then, teaches the positive aspects of friendship (vv. 1–10, esp. vv. 5–10), followed by the negative aspects in vv. 11–17.