Forest,
When was this man (the publican) justified? Remember, Jesus was speaking this before the cross.
Lk 18:10-14
10 Two men went up into the temple to pray; the one a Pharisee, and the other a publican.
11 The Pharisee stood and prayed thus with himself, God, I thank thee, that I am not as other men are extortioners, unjust, adulterers, or even as this publican.
12 I fast twice in the week, I give tithes of all that I possess.
13 And the publican, standing afar off, would not lift up so much as his eyes unto heaven, but smote upon his breast, saying, God be merciful to me a sinner.
14 I tell you, this man went down to his house justified rather than the other: for every one that exalteth himself shall be abased; and he that humbleth himself shall be exalted.
Titus 3:3-7
3 For we ourselves also were sometimes foolish, disobedient, deceived, serving divers lusts and pleasures, living in malice and envy, hateful, and hating one another.
4 But after that the kindness and love of God our Saviour toward man appeared,
5 Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Spirit;
6 Which he shed on us abundantly through Jesus Christ our Saviour;
7 That being justified by his grace, we should be made heirs according to the hope of eternal life.
Does this point to the believer's justification or are you going to concoct some other explanation for what you believe?