KJV 1 John 2:3 And hereby we do know that we know him, if we keep his commandments. 4 He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.
if by that one verse, you are saying salvation is gained by obedience to the laws, you are indeed speaking of the cursed Gospel. you would have to throw out a lot of other scriptures.
Galatians 2:21
I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain.