As Scripture makes clear, justification is a once for all time act, never to be repeated. It is not a continuing process. Lots of people don't like asparagus but there is something about asparagus that I consider to be amazing. He plants it once, and it is good for twenty or thirty years. Every Spring time without fail his asparagus comes up.
Justification is like asparagus-planting.
It is done only once. This does not mean, of course, that we can become careless about sin. Because we cannot. Rather, the person who is justified or accepted because of the obedience of Christ, strives to his or her utmost to lead a life that is pleasing to God. A God accepts us.