In the wake of a lone gunman’s slaughter of 59 people in Las Vegas Sunday night, Stephen Colbert opened Monday’s The Late Show challenging President Donald Trump be the president he promised to be, and pass gun control legislation.

“This afternoon the president called [the mass shooting] an act of pure evil. And I think he’s right,” Colbert began. “So what then are we willing to do to combat pure evil?” Colbert wondered.

Addressing Trump, Colbert said, “Doing nothing is cowardice. Doing something will take courage.”

“Now, President Trump, you said you want to be a transformative president, who doesn’t care about the way things have always been done in Washington D.C.” Colbert reminded.

“This is your chance to prove it. And I mean this sincerely. You do not owe the Republicans anything. You know the Republicans tried to stop you from being president. Well, screw ‘em!”

If Trump genuinely wants to Make America Great Again, Colbert suggested he “do something the last two presidents haven’t been able to do: pass any kind of common sense gun legislation that the vast majority of Americans want.”

Because we are facing pure evil, Colbert suggested that, by all means, Trump should offer his thoughts and prayers.

But, he advised POTUS, “think about what you ought to do, and then pray for the courage to do it.”