Grace is a person. His Name is Jesus. We have access to God through faith in Jesus Christ. Jesus was the sacrificial lamb that gave us access to God. Because of His finished works we now have a chance at eternal life.
Grace is not our way in, but rather our way out. In other words, grace is not an excuse to sin but, the power not to.
Unfortunately, many Christians are under the impression that grace means that they can do whatever they want to do, and still call themselves Christians, and still make it to heaven. Not so!
It's not their fault though. Many "leaders" are teaching a one-sided grace message. Many times for one of two reasons: They themselves have already sold their souls to the devil and they're purposely leading the people astray. They are living a double lifestyle themselves: Preaching the word of God behind the podium, while living any way they want to, outside of church. They are actually hoping that the message they are preaching is true, while knowing deep down inside, that it is not. They know (at least I hope they know) that they are going to hell and you are too, if you do not repent!
When we receive Jesus as our Savior, we are given the Holy Spirit to live on the inside of us. The Holy Spirit convicts us of sin. As a matter of fact, He is grieved with sin. There is no way a person can do the same thing over and over and still claim to have the Holy Spirit living on the inside of them. It's not even possible. He will depart from a person like that.
All have sinned and fallen short of the glory of God. (Romans 3:23) There is a difference in falling short and iniquity (continued ongoing sin after you know the truth). Repent means to turn completely away from something, not say "I'm sorry Lord," and continue doing that thing. No, grace does not cover that!
It tells us in the Bible "What shall we say then? Shall we continue in sin, that grace may abound? God forbid. How shall we that are dead to sin, live any longer there in? (Romans 6:1-2).