How did the Corinthians view immorality in their society?

Immorality was so woven into Corinthian society that the people were part and parcel of it and thought nothing different of it. They accepted it as normal, not as something abnormal, so Paul brought the gospel of grace into a city wracked with immorality.

Les explains that Corinth was a city wracked with immorality, and the Corinthians were part and parcel of their whole society; they thought nothing different of it. Into that setting Paul came with the gospel of the grace of God. Les points out that anything but grace would never have succeeded, but it was only by grace that God began to save these wicked Corinthians. He also draws a parallel between the physical and spiritual life: new believers are babes in Christ and will have failures, just as infants must grow.

What was the moral condition of Corinth?

Corinth was wracked with immorality, and its people were part and parcel of that immorality, thinking nothing different of it. They are described as wicked Corinthians, and only God's grace could save them; anything other than grace would never have succeeded.