From the article you linked:
By implementing the advice of another Stoic philosopher, the second-century slave-turned-teacher Epictetus, who admonished his students in this way: ‘Remember that it is we who torment, we who make difficulties for ourselves – that is, our opinions do. What, for instance, does it mean to be insulted? Stand by a rock and insult it, and what have you accomplished? If someone responds to insult like a rock, what has the abuser gained with his invective?’
Indeed. Of course, to develop the attitude of a rock toward insults takes time and practice, but I’m getting better at it. So what did I do in response to the above-mentioned rant? I behaved like a rock. I simply ignored it, focusing my energy instead on answering genuine questions from others, doing my best to engage them in constructive conversations. As a result, said prominent author, I’m told, is livid with rage, while I retained my serenity.
Instructions to Rahula:
"Rahula, develop the meditation in tune with earth. For when you are developing the meditation in tune with earth, agreeable & disagreeable sensory impressions that have arisen will not stay in charge of your mind. Just as when people throw what is clean or unclean on the earth — feces, urine, saliva, pus, or blood — the earth is not horrified, humiliated, or disgusted by it; in the same way, when you are developing the meditation in tune with earth, agreeable & disagreeable sensory impressions that have arisen will not stay in charge of your mind.