The Greek verb “ἐξαγοράζω”

Limited to Gal. 3:13; 4:5; Eph. 5:16; Col. 4:5, the Greek verb “exagorazo” meant “rescue,” “redeem,” “buy back,” “deliver.”

Christians are to “redeem the time” (Eph. 5:16; Col. 4:5); this is done by putting time to the best possible use.  The saved have this obligation because they have been “redeemed” from the law and its curse (Gal. 3:13; 4:5).  In these latter two verses there is “the idea of escape from the consequence of breaking God’s law” (Dictionary of New Testament Theology, 1:268).