The English gloss “perfect” is used less and less to translate Heb tam and Gk teleios in biblical texts referring to human beings (e.g., Noah, Job). Understandably so, since it strikes most readers (and exegetes) as out of place to refer to flawed human beings as “perfect.” In one place, however, this gloss stubbornly persists; namely, in Matt 5:48 (“be ye therefore perfect”). This paper will examine the interpretive background to this translation, possible reasons for its persistence in Matt 5:48, and will suggest alternatives for future translators.
Yinger, Kent, "‘Perfect’ in Matt 5:48: A Case for Mandatory Retirement" (2016). Faculty Publications - Portland Seminary. 69.