This is why a Child of God is the Righteousness of God by Faith in Christ Jesus (2 Cor. 5:21). In other words man cannot achieve this without being in Christ.
The Bible says in 2 Cor. 13:4, that Jesus was crucified through weakness. Which it had to be because Gods Grace is only made perfect in weakness. Therefore, through weakness Jesus was crucified that He may taste death by the Grace of God (Hebrews 2:9). As Children of God we get to taste that same death in Christ daily by picking up our own cross (which can only be done by trusting His Grace which is made perfect through our weakness by placing and maintaining our Faith exclusively in Christ and His Finished Work at Calvary Cross where the victory was won) and walking with Christ in the newness of life (His victory). Rom. 6:3-5, Rom. 8:17, Gal. 2:20-21, 2 Cor. 4:11, 2 Cor. 12:9-10, 2 Cor. 13:4, Hebrews 2:9
The fruit that a Child of God bears comes only by Righteousness which is by Grace (Gal. 2:21). Grace only comes through the weakness and death of Christ (2 Cor. 12:9-10). Therefore, Grace is only made perfect through weakness (not our flesh); but only by trusting and placing and maintaining our Faith exclusively in Christ and the Cross. This is the only way Grace flows in a Child of Gods life. This Child of God is considered weak, humble, and broken before God. (THE BEATITUDES MATTHEW 5)