רמב"ן — שפחה נחרפת לאיש / בקרת תהיה

Q — 'ביקרת תהיה לא יומתו.' What does ביקרת mean? Rashi and 'all the mefarshim': the bet din is to investigate the case carefully to avoid mistakenly imposing the death penalty on what looks like an eishet ish.

A — Ramban rejects: 'בידוע שיבוקר הדבר ולא ימיתו האדם חנם' — bet din always investigates. Instead, with a confident reach to Aramaic and Mishnaic Hebrew, Ramban reads בקרת as identical with הפקר/מופקרת — the letters בּ and פ regularly swap (as in 'הבקר לעניים הבקר' for hefker, in the Mishna). The shifcha charufa, half-slave and half-free, is 'מופקרת' to him — meaning legally she counts as not fully his wife (she's 'לא חופשה'). That's why no death penalty applies. Grammatical bonus: Rashi made בקרת the subject and תהיה the verb; Ramban makes the shifcha the subject and ביקרת the predicate (=מופקרת), with תהיה as copula.