He repays man according to his work,

10 “Therefore listen to me, you men of understanding:
Far be it from God to do wickedness,
And from the Almighty to commit iniquity.
11 For He repays man according to his work,
And makes man to find a reward according to his way.
12 Surely God will never do wickedly,
Nor will the Almighty pervert justice.

God's word is sure and it tells us that God will never do wickedly.
Man does.
You shall not pervert justice due the stranger or the fatherless, nor take a widow’s garment as a pledge. Deuteronomy 24:17, NKJV. {BLJ 168.1}

God’s word sanctions no policy that will enrich one class by the oppression and suffering of another. In all our business transactions it teaches us to put ourselves in the place of those with whom we are dealing, to look not only on our own things, but also on the things of others. Those who would take advantage of another’s misfortunes in order to benefit themselves, or who seek to profit themselves through another’s weakness or incompetence, are transgressors both of the principles and of the precepts of the Word of God. {BLJ 168.2}

Job 34:11 For the work of a man shall he render unto him, and cause every man to find according to [his] ways.

A Daily Inventory.--God judges every man according to his work. Not only does He judge, but He sums up, day by day and hour by hour, our progress in welldoing (RH May 16, 1899). {7BC 987.5}
12-15 (chs. 3:5; 13:8; 21:27; 22:19). The Book of Life.--When we become children of God, our names are written in the Lamb's book of life, and they remain there until the time of the investigative judgment. Then the name of every individual will be called, and his record examined, by Him who declares, "I know thy works." If in that day it shall appear that all our wicked deeds have not been fully repented of, our names will be blotted from the book of life, and our sins will stand against us (ST Aug. 6, 1885). {7BC 987.6}ob 34:11

so we have a trail and we are judged for are works in life . Why do we have to do this as we have asked for forgiveness of are sins?