1 Corinthians 15:10

"But by the grace of God I am what I am: and his grace which was bestowed upon me was not in vain; but I labored more abundantly than they all: yet not I, but the grace of God which was with me."

When we are given the gift of grace we are something new. The best thing we can do with this grace is to work through it. When we work now it is not our old self that work or do things for people but it was the grace of God that is working through you to reach the word. everything you spend hour witnessing to people, preparing lesson, planing ways to talk to people, even just reading your bible and learning something new every  time you turn those pages to find yourself  learning something each time. That is not us, but  the grace of God.