Mark 9:16-18 New American Standard Bible (NASB)

16. And He asked them, "What are you discussing with them?"

17. And one of the crowd answered Him, "Teacher, I brought You my son, possessed with a spirit which makes him mute;

18. and whenever it seizes him, it slams him to the ground and he foams at the mouth, and grinds his teeth and stiffens out. I told Your disciples to cast it out, and they could not do it."

Mark 9