King David reveals that "grace" doesn't suggest we are free to live in sin. Take a look at the many ways in just this passage that he expresses our need to be holy! (And how do we know what constitutes holiness? TORAH!)
Psalm 101: 1 A psalm of David: I am singing of grace and justice; I am singing to you, ADONAI. 2 I will follow the path of integrity; when will you come to me? I will run my life with a sincere heart inside my own house. 3 I will not allow before my eyes any shameful thing. I hate those who act crookedly; what they do does not attract me.
4 Deviousness will depart from me; I will not tolerate evil. 5 If someone slanders another in secret, I will cut him off. Haughty eyes and proud hearts I cannot abide. 6 I look to the faithful of the land, so that they can be my companions; those who live lives of integrity can be servants of mine. 7 No deceitful person can live in my house; no liar can be my advisor. 8 Every morning I will destroy all the wicked of the land, cutting off all evildoers from the city of ADONAI. (CJB)