There are people who think that, because we are under grace, how we live our lives is of no consequence.
Our lives matter and our works matter. Listen to what Jesus said, "These very works I am doing testify about Me that the Father has sent Me." According to Jesus, His works validated who He was. It that was true of Jesus, how much more true is that of you and me? If the works of Jesus certified His Messiahship, do not my works certify my Christian sonship? If my works do not substantiate that I am a Christian, then there is a good chance that I am not.
The Bible is clear that we will be judged by our works, not by our profession. We will be judged out of those things "written in the books" of our works (Revelation 20:12). And no amount of talk about "grace" is going to get us off the hook!
Before someone accuses me of being a heretic, let me be clear: we are saved by grace. But the grace that saves us is a productive grace. God's grace works in our lives to produce divine results--in particular, godly living. At the instant we are saved the Holy Spirit comes into our lives and begins producing the character of Jesus in us.
So the evidence of a genuine salvation is not only in what you profess, but also in what you do.
I heard someone say many years ago: "If you were arrested and accused to being a Christian, would there be enough evidence to convict you?"
Well, would there be?