Origen

“ The Parable Distinguished from the Similitude.
“Again the kingdom of heaven is like unto a treasure hidden in the field, which a man found and hid.” [1] The former parables He spoke to the multitudes; but this and the two which follow it, which are not parables but similitudes in relation to the kingdom of heaven, He seems to have spoken to the disciples when in the house. In regard to this and the next two, let him who “gives heed to reading” [2] inquire whether they are parables at all. ”