There was a stoning scene in the first season, though.
NO. THERE. WAS. NO. STONING. SCENE. (or at least not one in which anyone was actually stoned)
Yes, there was a scene in which the Handmaids were
ordered to stone Janine, for the crime of
endangering a baby. Janine kidnapped her daughter, Angela (whom Janine secretly named "Charlotte"), from the Putnam residence and fled. When caught, she climbed up on a bridge, intending to jump and kill both herself and the baby.
June convinced her to give Angela up, but was unable to convince her to get off the bridge rail. Janine jumped, survived, and was sentenced to stoning for endangering the baby.
June and the Handmaids were brought to the place where the Salvagings/Particicutions happen, and ordered to stone Janine. All of them held a rock, but June let hers fall to the ground. She said, "I'm sorry, Aunt Lydia," and refused to pick up the rock and throw it. The other Handmaids followed suit. Lydia prevented the idiotic guards from shooting everyone, though Ofglen #2 got her teeth knocked out for verbally protesting.
The Handmaids were dismissed, and Janine was taken away. We learned later that she'd been sent to the Colonies. The Handmaids were punished in various ways.
I've seen the first season multiple times, both watching it and from participating in discussions on several review channels. Honestly, NOBODY WAS STONED. Nobody killed a baby. We saw just a couple of episodes ago that Angela is alive and well, as Janine was allowed to hold her for a few minutes at the Putnams' house.