Proverbs 21:21 He that followeth after righteousness and mercy findeth life, righteousness, and honor.
If you follow after righteousness (Law) and mercy (Gospel), then you will find life, righteousness, and honor. You tend to find what you are looking for. If you look for Law and Gospel in the Scripture, you will find Law and Gospel.
The Law promises righteousness and life, but if you look for righteousness and life in yourself you will never find it, and you end up only dead and hating God. The Law cannot give it, so the Law becomes a dire threat. The Gospel promises righteousness and life, and the Gospel gives it, for if you look for righteousness and life in God you will find it. The Gospel gives it, you have the righteousness of God and the life of God by faith, so the Gospel becomes a wonderful promise.
Therefore, we look for everything we need, all that pertains to life and godliness, in Christ. “Seek ye first (and last, and always, and only) the kingdom of God and his righteousness, and all these things shall be added unto you.” Follow, by hearing the Law and repenting, and by hearing the Gospel and believing. Hear it in your head and in public assembly as often as you can. Then the promise of righteousness, life, and honor is yours, it’s real, and it’s alive. Enjoy it.