"Perfect righteousness" refers to someone who always makes morally right choices and behaves in an ideal and flawless manner in terms of ethics and morality. Full definition
It is only the absolute perfect righteousness of Christ that can satisfy the demands of a perfect God. (redeeminggod.com)
Jesus lived in perfect righteousness, and tells us that if we believe in Him, He gives that righteousness to us» (John 3:16; 5:24; 6:47; 2 Cor 5:21). (redeeminggod.com)
The fourth truth to be impressed upon people is that God demands perfect righteousness from us in order to spend eternity with him. (redeeminggod.com)