Mark 4:10

"And when he was alone, they that were about him with the twelve asked of him the parable."

Cross References (ranked by relevance)

Then Jesus sent the multitude away, and went into the house: and his disciples came unto him, saying, Declare unto us the parable of the tares of the field.

Mark 4:34

But without a parable spake he not unto them: and when they were alone, he expounded all things to his disciples.

Mark 7:17

And when he was entered into the house from the people, his disciples asked him concerning the parable.

Proverbs 13:20

He that walketh with wise men shall be wise: but a companion of fools shall be destroyed.