Self-Holiness (sanctification) is the other requirement for salvation besides confession of Jesus

Follow after peace with all men, and the sanctification without which no man shall see the Lord: Hebrews 12:14

Holiness is attained by keeping 100% of the commandments or rules in Moses and the Prophets and in the New Testament (Numbers 15:40, Luke 16:29-31).

Self-Holiness (sanctification) is the goal of the RIGHTEOUSNESS of Jesus

Jesus died in the place of man to make it possible for mankind to become holy, live holy, and die holy emulating Jesus because Jesus already paid for the penalty of the past sins of the men who came unto repentance to become a brand-new holy creature.

It is not true that men cannot become holy because they are sinners by nature

Yes, all men are sinners but Jesus came to bring all men from being sinners to become new holy creatures upon repentance, if men manage to not go back to their previous sins or sin new sins.

Holiness is one of the commandments

A commandment of God must be carried out by men and not by Jesus for men. ‘Be ye holy!’ is one of the commandments to keep. As a commandment, mankind must keep and observe it and NOT believe that Jesus will keep the commandment of holiness for us.