mid-14c., reproche, "a rebuke, blame, censure" directed against a person; also "object of scorn or contempt;" c. 1400, as "disgrace, state of disgrace," from Anglo-French repruce, Old French reproche "blame, shame, disgrace" (12c.), from reprochier "to blame, bring up against."
OED cites Diez for the explanation that this is from Vulgar Latin *repropiare, from Latin re- "opposite of" + prope "near" (see propinquity), with suggestions of "bring near to" as in modern get in (someone's) face. But it points out other etymologists of French would have it from *reprobicare, from Latin reprobus/reprobare "disapprove, reject, condemn" (see reprobate (adj.)).
mid-14c., reprochen, "charge with a fault, censure severely," from Anglo-French repruchier, Old French reprochier "upbraid, blame, accuse, speak ill of," from reproche "blame, shame, disgrace" (see reproach (n.)). The sense of "rebuke, revile, abuse" is from 1510s. Related: Reproached; reproaching; reproachable.
To reproach a person is to lay blame upon him in direct address, and with feeling, to endeavor to shame him with what he has done. [Century Dictionary]