What a marvelous truth! Jesus cried, "It is Finished!", as He neared His death while experiencing excruciating pain on the Cross. These words are treasured by every child of God. What a Savior and Friend we do have.
Here are some words from Martin Luther on this verse:
"How can I buy for a farthing that which cost many thousand talents of gold? The law, with all the works and righteousness thereof, is but as a farthing, if we compare it to Christ, who by His death has vanquished my death and has purchased righteousness and everlasting life. Should I then despise and reject this incomparable price, and by the law, or by the works and merit of men (vile dross and dung, for so Paul calls them, if they be compared unto Christ), seek that righteousness which Christ freely and of mere love has given unto me already, and has cost Him so great a price, that He was constrained to give Himself, and even His own heart-blood for me!"-Martin Luther, From his commentary of Galatians.