1 Therefore thou are inexcusable, O man, whoever thou are that judges: for when thou judge another, thou condemn thyself; for thou that judges do the same things.
The word "Judge" has 2 meanings; decide between or condemn. The Bible is clear that we ARE to decide between good and evil, even telling others when they are in danger of hell because of their sin. But we are NOT to condemn others. Our actions should always be motivated by love and a sincere desire to bring others to God. Treating others with a spirit of condemnation is really setting ourselves up as superior to them. We aren't. All humans are of equal value in the eyes of God.
2 But we are sure that the judgment of God is according to truth against them which commit such things.
We know whatever judgement God gives our is righteous. He set the standard and He wrote the rules. But He is also love and kindness. So if He says something is evil, He has a good reason even if we don't understand it.
3And think thou this, O man, that judges them which do such things, and do the same, that thou shalt escape the judgment of God?
"Do you really think that you can condemn those who sin while you are committing the same sin and you will escape God's condemnation?"
4 Or despise thou the riches of His goodness, restraint, tolerance, and patience, not knowing that the goodness of God leads thee to repentance?
It's God's goodness that makes people turn from their evil ways.
5 But after thy hardness and unrepentant heart treasures up unto thyself wrath against the day of wrath and revelation of the righteous judgment of God;
The sinner ignores God goodness and continues to add more and more of God's wrath to his account.
6 Who will render to every man according to his deeds:
God will give each human what he deserves according to what he has done in his life.
7 To them who by patiently continue in well doing, seeking for glory, honor, and immortality, (He gives) eternal life:
8 But unto them that are contentious, and do not obey the truth, but obey unrighteousness, (He gives) indignation and wrath,
9 Tribulation and anguish, upon every soul of man that does evil, of the Jew first, and also of the Gentile;
Both Jews and Gentiles will be punished alike, by the same standard. It doesn't matter what your genes are.
10 But (He gives) glory, honor, and peace, to every man that works good, to the Jew first, and also to the Gentile:
11 For there is no respect of persons with God.
God simply doesn't care what your bloodlines are. He cares what your heart is.
12 For as many as have sinned without (the Mosaic) law shall also perish without law: and as many as have sinned in the law shall be judged by the law;
If you sin without knowing about the Law given to Moses you die because you have no law in your life. If you sin while knowing about The Law, you die because you broke The Law. No human is innocent.
13 (For not the hearers of the law are just before God, but the doers of the law shall be justified.
God doesn't care about our knowledge, but about our actions.
14 For when the Gentiles, which have not the law, do by nature the things contained in the law, these, having not the law, are a law unto themselves:
Jesus said that If you love God with all you've got and love your neighbor as yourself, you have fulfilled The Law. So when someone who has never heard of The Law obeys those two commands, they are automatically completing the whole Law. When we give our hearts to God, our nature is changed and we want to love God with all we have and we develop a love for our neighbors as precious creations of our God.
15 Which show the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another;)
The gentile believers have God's law written on their heart, so they obey The Law without ever having even heard of it.
16 (a continuation of verse 12, 13-15 being an interjection. So... "For as many as have sinned without (the Mosaic) law shall also perish without law: and as many as have sinned in the law shall be judged by the law...) In the day when God shall judge the secrets of men by Jesus Christ according to my gospel.
The Jews and the Law
17 Behold, thou are called a Jew, and rest in the law, and make thy boast of God,Paul's audience is the Jews in Rome.
18 And know his will, and approve the things that are more excellent, being instructed out of the law;
The Jews start with an advantage simply because they grow up with a biblical world view. The gentiles have to learn a whole new way of thinking, looking at things. The Jews already know what God wants because of the Law.
19 And are confident that thou thyself are a guide of the blind, a light of them which are in darkness,
The Jews are to teach the gentiles what righteousness is.
20 An instructor of the foolish, a teacher of babes, which has the form of knowledge and of the truth in the law.
21 Thou therefore which teach another, teach thou not thyself? Thou that preach a man should not steal, do thou steal?
22 Thou that say a man should not commit adultery, do thou commit adultery? Thou that abhors idols, do thou commit sacrilege?
23 Thou that make thy boast of the law, through breaking the law dishonor thou God?
"Are you being hypocrites?"
24 For the name of God is blasphemed among the Gentiles through you, as it is written.
25 For circumcision verily profits, if thou keep the law: but if thou be a breaker of the law, thy circumcision is made uncircumcision.
It only does you any good to keep the Law if you keep the whole Law. And no one can keep the whole Law. So when you break it, it's like you were never even circumcised.
26 Therefore if the uncircumcision keep the righteousness of the law, shall not his uncircumcision be counted for circumcision?
So, then, the reverse is true too; if those who were never circumcised are righteous, doesn't that count the same as being circumcised?
27 And shall not uncircumcision which is by nature, if it fulfill the law, judge thee, who by the letter and circumcision dost transgress the law?
This "judge" does not mean "sit in a judge's seat and condemn." It means that by the gentiles example of living a righteous life, it proves it is possible for the Jews to live such a life, if they only accept Jesus. The Jews can't stand before God on judgement day and say, "It just wasn't possible in my time to live that way."
28 For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh:
29 But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.
God does not see someone as a "Jew" who has the genetic coding descended from Abraham. Rather, He sees someone as a "Jew" who lives by the spirit, the meaning of the law, namely "Love God with all you've got, and love your neighbor as yourself."