If I speed past you doing 185mph and you pull me over after chasing me for 120 miles; discover when questioning me that I am stoned, I have a loaded rifle on the seat next to me, and my pitbull leaps out of the car and takes a piece out of your leg, I think I'd be in trouble.
But you, being the kind guy you are and feeling sorry for me because my favourite second cousin twice removed died just recently 9 years ago and because I am still grieving, decide to let me off. That's grace. Lotssa grace.
I then let out a whoop, shout "praise cops everywhere" , proclaim my freedom from the law, take off in a hail of metal and smoke, do 3 360's in the middle of the freeway in celebration and accelerate to 250 mph while continuing to proclaim my freedom from being under the law because I am now under grace.
The point being that we are saved by the grace of God through the most precious blood of Jesus. What next? Celebrate and care not for obedience? Proclaim the law a bad thing (as many do) and celebrate my freedom? Or obey the law of God out of a grateful heart by His grace and power and be called a 'legalist' by those who who don't seem to understand.
Ro 3:31 Do we then make void the law through faith? God forbid: yea, we establish the law.
Rom 6:17 But God be thanked, that ye were the servants of sin, but ye have obeyed from the heart that form of doctrine which was delivered you.
18 Being then made free from sin, ye became the servants of righteousness.
19 I speak after the manner of men because of the infirmity of your flesh: for as ye have yielded your members servants to uncleanness and to iniquity unto iniquity; even so now yield your members servants to righteousness unto holiness.
20 For when ye were the servants of sin, ye were free from righteousness.
21 What fruit had ye then in those things whereof ye are now ashamed? for the end of those things is death.
22 But now being made free from sin, and become servants to God, ye have your fruit unto holiness, and the end everlasting life.
23 For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
When Jesus said "If ye love Me, keep My commandments" I don't recall anyone complaining because they might be branded a 'legalist'.