It is not that we earn grace or salvation - I would argue strongly that every effort of “struggle” is itself an effort made possible and infused with grace. But the gift of our salvation should not be likened to a man who never picked up a baseball bat suddenly walking up to the plate at the last out in the ninth inning, facing a pitcher with an ERA below 1 and smacking the baseball deep into the stands in center field. I’ll grant that grace could work like that, but it would be Walt Disney and not Jesus Christ. Thus the God who saves us by grace tells us to “keep my commandments,” and any number of other things. [An exception: the wise thief. Ninth inning. Though even he surely knew a struggle as he fought his way to the words: “Remember me in your kingdom.”] God will not abandon us as we take up that struggle - but struggle we must - for such is the life of grace.

http://fatherstephen.wordpress.com/2007/06/30/the-struggle-for-communion/