The story of the two cities of Sodom and Gomorrah can be found in the book of Genesis 19.
These two cities were eventually destroyed by fire and brimstone because of their unrepentant sinfulness and evil deeds.
In the 1st reading, the prophet Isaiah used the symbolic names of these two cities to warn his people of the anger and the judgment of God that will come upon them if they don't repent.
Even God Himself seemed to be pleading through the prophet Isaiah with these words:
Come now, let's talk this over. Though your sins are like scarlet, they shall be white as snow; though they are red as crimson, they shall be white as wool.
We may not be committing the kind of atrocious sins of the cities of Sodom and Gomorrah.
Yet, it does not mean that the lesser or venial sins are acceptable in the eyes of God.
The human tendency to crave for recognition and status is what Jesus pointed out in the gospel.
Jesus also pointed out that we have this tendency to be self-righteous and even impose our religious beliefs onto the weaker ones when they don't share our views of religious practices.
These may not seem to be major sins but they reveal to us our understanding of our Master.
Jesus our Master came to serve and not to be served.
May we follow our Master and be servants to each other in love and humility.