Mark 9:28

28 After Jesus had gone indoors, his disciples asked him privately, "Why couldn't we drive the spirit out?"

Mark 9:28 Meaning and Commentary

Mark 9:28

And when he was come into the house
Perhaps into the man's house whose child he had healed, or into some other in these parts, for the sake both of retirement and refreshment:

his disciples asked him privately, why could not we cast him out?
The nine disciples, who were particularly concerned in this matter, fearing they had lost the power of casting out devils, conferred upon them, inquired of Jesus, when he was alone, why they could not cast the demon out of the child, when they had ejected unclean spirits out of many others; (See Gill on Matthew 17:19).

Mark 9:28 In-Context

26 The spirit screamed, threw the boy into a bad fit, and came out. The boy looked like a corpse, and everyone said, "He is dead!"

27 But Jesus took the boy by the hand and helped him rise, and he stood up.

28 After Jesus had gone indoors, his disciples asked him privately, "Why couldn't we drive the spirit out?"

29 "Only prayer can drive this kind out," answered Jesus; "nothing else can."

30 Jesus and his disciples left that place and went on through Galilee. Jesus did not want anyone to know where he was,