Divine grace is the sovereign and saving favor of God exercised in the bestowment of blessings upon those who have no merit in them and for which no compensation is demanded from them.  Nay, more; it is the favor of God shown to those who not only have not positive deserts of their own, but who are thoroughly ill-deserving and hell-deserving. 

It is completely unmerited and unsought, and is altogether unattracted by anything in or from or by the objects upon which it is bestowed.  Grace can neither be bought, earned, nor won by the creature.  If it could be, it would cease to be grace. 

When a thing is said to be of "grace" we mean that the recipient has no claim upon it, that it was in nowise due him.  It comes to him as pure charity, and, at first, unasked and undesired.

Pink, Arthur W.  The Attributes of God.  Grand Rapids:  Baker Book House.  1975.  p. 66.