In previous verses it was demonstrated that Jews have much advantage over the Gentiles, but neither Jews nor Greeks (Gentiles) are better than the other, because all sinned.
The Scriptures themselves (given to the Jews) proclaim that:
There is none righteous, all have turned aside and together became useless, there is no one which understands or seeks after God, there is none who does good (Psalm 14: 1-3). If it were not for the grace of God, who through His Son "came to seek and to save that which was lost" (Luke 19:10), all humanity would be destined to everlasting destruction.
Their throats are open tombs, their tongues are deceitful, poison, cursing and bitterness (Psalm 5:9, 140:3, 10:7). "They sharpen their tongues like a serpent; The poison of asps is under their lips." (Psalm 140:3). Today this rot spreads generally and is emphasized by newspapers, radio, television, cinemas, internet, etc.,
They are bloodthirsty and destructive, ignoring the way of peace (Isaiah 59:7-8). This has been abundantly manifested in today's wars and revolutions.
They do not fear God. "The transgression of the wicked is affirming within my heart, `Fear of God is not before his eyes'" (Psalm 36:1 YLT). Is the reality aggravated even more by the atheism and humanism of today.
The law given through Moses had intended to demonstrate that everyone is guilty before God, that "There is none righteous, not even one" (v. 10); no one can be justified before God for his actions, because the law brings full knowledge of sin.
This description of the state of humanity is a list extracted from some psalms and the prophecy of Isaiah, well known to Jews as the Psalms were sung and the prophecy was read (and still are) in their Sabbath meetings in the synagogues.
They are the symptoms of the evil that is in all men, whatever their race, culture, knowledge of God or location "for all have sinned and fall short of the glory of God" (v. 23). They are found in all human history.
In war: the elimination of the innocent, atrocities, torture, sadism, etc..
Social crimes: murder, mutilation, theft, robbery,embezzlement, vandalism, corruption, etc..
Domestic cruelty: disloyalty, divorce, mental torture, violence, child abuse, etc..
Harmful behavior to themselves and others, dunkenness, addiction to drugs and tobacco, arrogance, insolence, greed, ingratitude, hatred, environmental pollution, racism, etc..
Pernicious language: obscenity, lies, blasphemy, cursing, swearwords, gossip, dirty jokes, imprecations, etc..
Sexual immorality: adultery, homosexuality, bestiality, rape, prostitution, debauchery, pornography, etc..
The list seems endless, unanswerable proof of the increasing depravity of mankind up to the present day.
The law of Moses was given to the people of Israel, and all that is contained therein apply to this people. Israel was a special people, originated by a miracle performed in the elderly and barren Sarah, Abraham's wife, to serve as a model and example for all humanity. The law was given to show the standard of conduct that was required of that people, and highlighted their sin, because they never got to meet what it demanded.
From this point of view Israel was a sample of all mankind, and like Israel, a people blessed with the knowledge and the very Word of God, sadly failed to achieve the perfect measure of God, the rest of humanity, deprived of this advantage, was also found in sin and short of the glory of God. It is as if we took a sample of water from a well, and even after treatment, it still showed itself polluted. Of course all the water that was in the well was also polluted.
From this it is understood that the law was given as a measure for those who received it, who were the people of Israel, but the knowledge of it makes the whole world, Jews or Gentiles, aware that they are sinners, that is, their conduct falls short of perfection, and therefore they are subject to the judgement of God.
The law was not given to justify people but to produce the knowledge of sin. As a ruler proves that a line is crooked, a mirror shows that the face is dirty and a thermometer shows that we have a fever, the law shows us our sinful state. The ruler does not straighten the line already drawn, the mirror does not clean the face, nor does the thermometer cure the fever. Also the law cannot justify us before God.
No one, whether Jew or Gentile, can justify himself, ie, by ceasing to sin completely and becoming righteous through complete obedience to the law of Moses. Even in the case of changing to the point of paying perfect obedience, all the faults committed previously will still be subject to judgement. The good works that he might do will only be a part of his new character and there is no way to compensate for previous sins with them. He continues guilty before God.
But do not despair: we learn further along how justification is possible, by the grace of God, offered freely to all who seek it.
9 What then? Are we better than they? Not at all. For we have previously charged both Jews and Greeks that they are all under sin.
10 As it is written: "THERE IS NONE RIGHTEOUS, NO, NOT ONE;
11 THERE IS NONE WHO UNDERSTANDS; THERE IS NONE WHO SEEKS AFTER GOD.
12 THEY HAVE ALL TURNED ASIDE; THEY HAVE TOGETHER BECOME UNPROFITABLE; THERE IS NONE WHO DOES GOOD, NO, NOT ONE."
13 "THEIR THROAT IS AN OPEN TOMB; WITH THEIR TONGUES THEY HAVE PRACTICED DECEIT"; "THE POISON OF ASPS IS UNDER THEIR LIPS";
14 "WHOSE MOUTH IS FULL OF CURSING AND BITTERNESS."
15 "THEIR FEET ARE SWIFT TO SHED BLOOD;
16 DESTRUCTION AND MISERY ARE IN THEIR WAYS;
17 AND THE WAY OF PEACE THEY HAVE NOT KNOWN."
18 "THERE IS NO FEAR OF GOD BEFORE THEIR EYES."
19 Now we know that whatever the law says, it says to those who are under the law, that every mouth may be stopped, and all the world may become guilty before God.
20 Therefore by the deeds of the law no flesh will be justified in His sight, for by the law is the knowledge of sin.
Romans chapter 3, verses 9 to 20