consenting adj.

c. 1300, "agree, give assent; yield when one has the right, power, or will to oppose," from Old French consentir "agree; comply" (12c.) and directly from Latin consentire "agree, accord," literally "feel together," from assimilated form of com "with, together" (see con-) + sentire "to feel" (see sense (n.)).

"Feeling together," hence, "agreeing, giving permission," a sense evolution that apparently took place in French before the word reached English. Related: Consented; consenting.