Spider in the bathroom

This morning, he asked me if he had permission to kill a spider in the bathroom. I was in the other room, so I needed more information.
"Is it big and fast, or is it of a size that you could catch with a lid and glass?" I asked.
"Big and fast."
"Permission granted." pause, re-think. "I mean, could you try to catch it first and if that doesn't work, just stomp on it?"
"Okay." A few minutes go by. He enters the bedroom where baby and I are biding our time to show a creepy spider doing 360s inside a capped glass baby food jar.
"Okay. Great. Don't get any closer."
He smiles.
"Okay, go ahead and take him outside!" I say, calmly.
"So he can drown in this downpour?"
"Yes, a slow, painful death to the spider." The words slipped out before I had much time to think about them. I'm certainly not up for a pet in a baby jar.
"Out he goes."
Good thing its still raining.