Nang
TOL Subscriber
There is a thing that differs in these issues.
That difference being the difference between a thing that is based on one and the same foundation, and a thing that contains one and the same content as another, or not.
One case in point of many that could be cited - Romans 3:21's "But NOW, the righteousness of God WITHOUT the law..."
I believe you should read Romans 3:21-31, for the point you attempt to make does not stand.
That DIFFERS IN CONTENT from...
Romans 10:5 For Moses describeth the righteousness which is of the law, That the man which doeth those things shall live by them.
Nope. No difference, other than no man can achieve righteousness by keeping the Law . .not because there is no righteousness in the Law . . but because all men are unable and unwilling to live according to the righteousness of the Law (to establish the Law).
Only one Man had the virtue and capacity and power to do so, and He has imputed His righteousness (performed according to and under the Law) to us by His grace.
None of any of this changes the Gospel message of grace a whit.