8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
By our faith, we have access to God's grace. What is God's grace?
Well lets check this invaluable resource wikipedia:
Grace in Christianity is the free and unmerited favour of God as manifested in the salvation of sinners and the bestowing of blessings. Common Christian teaching is that grace is unmerited mercy (favor) that God gave to humanity by sending his son to die on a cross, thus delivering eternal salvation. Bill Gothard, an American conservative Christian, has suggested "God's grace gives us the desire and the power to do his will."
I could not have said it better myself. Here is the link to wikipedia to read it for yourself.