Matthew 17:19

Then Jesus' disciples came to Him privately and said, "Why could we not drive out that evil spirit?"

And when He was alone those people who gathered around Him, along with the twelve apostles, asked Him what the parables meant.

And when Jesus had come into a house, His disciples asked Him privately, "Why could we not drive out the evil spirit [from that boy]?"

Treasury of Scripture Knowledge

Then came the disciples to Jesus apart, and said, Why could not we cast him out?

And when He was alone those people who gathered around Him, along with the twelve apostles, asked Him what the parables meant.

And when Jesus had come into a house, His disciples asked Him privately, "Why could we not drive out the evil spirit [from that boy]?"