The righteousness of Jesus is 100% perfection. Jesus never sinned, even in His fully God/fully man state here on earth. Sure, He was tempted like we are. In fact, He was tempted A LOT – by natural human desire, by other people, and even by Satan himself (something I hope most of us have not experienced!).
During all of His times of temptation, He never once sinned, and He responded both with grace and with Scripture quotations. He realized that when we draw near to God through His Holy Word, God draws near to us and gives us the strength to resist temptation. Through His avoidance of wrongdoing, we see clearly how Jesus did not have any sins of commission in His life (doing something wrong that goes against God’s commands).
From the time of His birth here on earth, both Jesus and His human parents carefully followed the Old Testament laws and customs to the T. While He was an infant, Jesus’ parents took care to circumcise Him on the correct day, offer the appropriate sacrifice at the Temple, and so much more. Jesus did not have any sins of omission (not doing something you know is commanded by God).
Jesus was able to be the faultless, sinless, blameless sacrifice for our sins because He was without sin. As the perfect sacrifice, Jesus took all of our sins on Himself at the cross, so that when God looks at the redeemed, He sees faultlessness, rather than our sins; He sees Jesus, not us. God now sees us followers of Jesus Christ as perfect, sinless, and worthy, because Jesus Christ is all of those things and more. In all sincerity, thank God for that!