Question further to Turch looking at revenge

Hello Rabbi Michi,
A question I’ve been grappling with for a long time: How do we know what is morally forbidden?
Is it according to our “moral intuition”? After all, one person’s moral intuition is not necessarily similar to another person’s and is very dependent on emotion and culture.
For example, in the time of our ancestors it was moral to punish sons for the sins of their fathers, but today it is not.