King James Version (KJV)
Iron sharpeneth iron; so a man sharpeneth the countenance of his friend.
Modern English
Iron sharpens iron, and one man sharpens another.
Hebrew
בַּרְזֶ֣ל בְּ֭בַרְזֶל יָ֑חַד וְ֝אִ֗ישׁ יַחַ֥ד פְּנֵי רֵעֵֽהוּ׃
barzel bbarzel yaḥad vʾiysh yaḥad pney reʿehv