Justification by presumption, i.e., self-justification, is justifying self while judging others.
Justification by faith, on the other hand, teaches one to justify others and to judge self.
Now Jesus was selfless. Jesus justified us by faith. He judged Himself while He justified others.
“For He hath made Him [to be] sin for us, who knew no sin; that we might be made the righteousness of God in Him.” 2Cor 5:21
“Let this mind be in you, which was also in Christ Jesus…” Phil 2:5
“…in lowliness of mind let each esteem other better than themselves.” Phil 2:3