Catholic Christians see justification, sanctification (and glorification) as three aspects of the same process begun at the same moment in time. Protestant Christians see the three aspects as successive phases of salvation.
Catholics believe that when God declares a person just, He makes him/her just.
Romans 2:5-13
By your stubbornness and impenitent heart, you are storing up wrath for yourself for the day of wrath and revelation of the just judgment of God, who will repay everyone according to his works: eternal life to those who seek glory, honor, and immortality through perseverance in good works,  but wrath and fury to those
who selfishly disobey the truth and obey wickedness.
Yes, affliction and distress will come upon every human being who does evil, Jew first and then Greek. But there will be glory, honor, and peace for everyone who does good, Jew first and then Greek. There is no partiality with God.  All who sin outside the law will also perish without reference to it, and all who sin under the law will be judged in accordance with it.  For it is not those who hear the law who are just in the sight of God; rather, those who observe the law will be justified.