Thayer's Greek Lexicon

 1. to redeem
  1) by payment of a price to recover from the power of another,
to ransom, buy off
  2) metaph. of Christ freeing the elect from the dominion of the
Mosaic Law at the price of his vicarious death
2. to buy up, to buy up for one's self, for one's use
  1) to make wise and sacred use of every opportunity for doing
good, so that zeal and well doing are as it were the purchase
money by which we make the time our own