The moral decay of the inhabitants of the plain serves as a dark prelude to the impending destruction of Sodom, standing in sharp contrast to the righteousness of Abraham. Highlighting the disgrace of these people at this stage is primarily meant to condemn Lot for choosing to settle among them. At the same time, it emphasizes the merit of Abraham, whose destiny was deliberately separated from such a corrupt environment [רמב״ן, רש״י, מזרחי]. Furthermore, pointing out their severe flaws applies the principle that the memory of the wicked should be a warning. By explicitly noting their disgrace, people are distanced from ever imitating their behavior [רש״י, תורה תמימה, ברכת אשר].
The specific nature of their crimes encompassed a total moral collapse. Some commentators suggest they were thoroughly corrupt both toward God and toward their fellow human beings, violating fundamental laws through robbery, bloodshed, and idolatry [רד״ק]. Others draw a distinction between their offenses, viewing one aspect of their behavior as crimes between man and man, and another as sins directed against God [נתינה לגר, יהל אור, חזקוני]. The primary approach among commentators is that their wickedness was expressed through physical transgressions, such as immorality and violence, while their sinfulness manifested in financial crimes and theft [רש״י, העמק דבר, שפתי חכמים]. Conversely, another tradition reverses this, suggesting their foundational evil lay in their financial cruelty, marked by extreme stinginess and a complete refusal to host guests or help the poor, alongside physical sins [גור אריה, ברטנורא, קצור בעל הטורים]. From a broader social perspective, they formed a society completely devoid of moral principles, acting entirely out of base desires and sowing social destruction [רש״ר הירש]. Another layer of interpretation views the dual description of their actions as a reflection of their ultimate punishment. They were wicked in this world and will be considered sinners in the World to Come, leaving them with no share in the future [תורה תמימה].
Their rebellion reached an extreme level, characterized by a deliberate intent to anger God despite recognizing His authority [רש״י, תורה תמימה]. Their actions were committed publicly and constantly [רד״ק], making them far worse than the other inhabitants of Canaan [קרני אור]. While a normal society might be slightly restrained by the fear of other people, the inhabitants of Sodom broke all boundaries in their defiance of God, acting without any restraint whatsoever [רש״ר הירש]. Some interpret the severity of their actions as an expression of sheer magnitude, indicating that their wickedness was enormous even if they did not actually know God [שד״ל]. Another perspective reveals a tragic irony, noting that they were profoundly evil toward their fellow human beings, yet outwardly presented themselves as righteous and exceedingly close to God [ברכת אשר]. Finally, it is suggested that at this early stage, the absolute magnitude of their corruption was known exclusively to God. Because their wickedness was not yet recognized by the rest of the world, God allowed them to continue until the full outcry of their victims would eventually reach Him [קונטרס חיבה יתירה].