The Pharisee and the Publican - Luke
Luk 18:9 And he spake this parable unto certain which trusted in themselves that they were righteous, and despised others:
Luk 18:10 Two men went up into the temple to pray; the one a Pharisee, and the other a publican.
Luk 18:11 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.
Luk 18:12 I fast twice in the week, I give tithes of all that I possess.
Luk 18:13 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.
Luk 18:14 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.
A Pharisee = A greater sinner than the publican (Mat 23:13-15)
I fast, give tithes = acts having no bearing on justification (Rom 3:28)
God be merciful to me a sinner = a prayer of repentance and calling on Jesus for salvation (Mat 9:13) (Luke 24:44-47) (1 Cor 15:1-4)
In other words:
Pride is a red warning light of sin, specially for those in position of religious authority.
Mat 23:13 But woe unto you, scribes and Pharisees, hypocrites! for ye shut up the kingdom of heaven against men: for ye neither go in yourselves, neither suffer ye them that are entering to go in.
Mat 23:14 Woe unto you, scribes and Pharisees, hypocrites! for ye devour widows' houses, and for a pretence make long prayer: therefore ye shall receive the greater damnation.
Mat 23:15 Woe unto you, scribes and Pharisees, hypocrites! for ye compass sea and land to make one proselyte, and when he is made, ye make him twofold more the child of hell than yourselves.
Rom 3:28 Therefore we conclude that a man is justified by faith without the deeds of the law.
Mat 9:13 But go ye and learn what that meaneth, I will have mercy, and not sacrifice: for I am not come to call the righteous, but sinners to repentance.
Luk 24:44 And he said unto them, These are the words which I spake unto you, while I was yet with you, that all things must be fulfilled, which were written in the law of Moses, and in the prophets, and in the psalms, concerning me.
Luk 24:45 Then opened he their understanding, that they might understand the scriptures,
Luk 24:46 And said unto them, Thus it is written, and thus it behoved Christ to suffer, and to rise from the dead the third day:
Luk 24:47 And that repentance and remission of sins should be preached in his name among all nations, beginning at Jerusalem.
1Co 15:1 Moreover, brethren, I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand;
1Co 15:2 By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.
1Co 15:3 For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures;
1Co 15:4 And that he was buried, and that he rose again the third day according to the scriptures: