Mark 9:28

28 After Jesus had gone indoors, his disciples asked him privately, “Why couldn’t we drive it out?”

Read Mark 9:28 Using Other Translations

And when he was come into the house, his disciples asked him privately, Why could not we cast him out?
And when he had entered the house, his disciples asked him privately, "Why could we not cast it out?"
Afterward, when Jesus was alone in the house with his disciples, they asked him, “Why couldn’t we cast out that evil spirit?”

What does Mark 9:28 mean?

John Gill's Exposition of the Bible
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).

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