That is Obedience to the law being evidence of one who has imparted righteousness.
Barney, what else would you expect other than obedience to the law if God, in His great loving grace and mercy to the the repentant sinner, grants him power to become a child of God? ....
....what else would you expect other than obedience to the law if God in His grace infused the believing child with His love?....
....what else would you expect other than obedience to the law if God by His great and wondrous power fulfills His promise to the believer that he would be filled with all the fullness of God?.....
....what else would you expect other than obedience to the law if God in accordance to the prophecy of Peter made the repentant sinner a partaker in the divine nature?.....
....what else would you expect other than obedience to the law if God in mercy forgives sin and cleanses the sinner from all unrighteousness?.....
.....what else would you expect other than obedience to the law if God in accordance to His promise in Romans granted us His power that the righteousness of the law might be fulfilled in us who walk not after the flesh but after the Spirit?....
....what else would you expect other than obedience to the law if God in His benevolence and faithfulness conforms the faithful believer into the image of God's Son?....
....what else would you expect other than obedience to the law if God in fulfilling His own word destines repentant sinners to keep the company of holy angels for all eternity?....
....what else would you expect other than obedience to the law if God in His mercy saves men and women from their sins?....
....what else would you expect other than obedience to the law if God in keeping His promise through His Son fills His hungering and thirsting children with His own righteousness?....
....what else would you expect other than obedience to the law if we walk as He walked?....
97 ¶ MEM. O how love I thy law! it is my meditation all the day.
98 ¶ Thou through thy commandments hast made me wiser than mine enemies: for they are ever with me.
99 I have more understanding than all my teachers: for thy testimonies are my meditation.
100 I understand more than the ancients, because I keep thy precepts.
101 ¶ I have refrained my feet from every evil way, that I might keep thy word.
102 ¶ I have not departed from thy judgments: for thou hast taught me.
103 ¶ How sweet are thy words unto my taste! yea, sweeter than honey to my mouth!
104 Through thy precepts I get understanding: therefore I hate every false way.