Mark 4:21 - Ellicott's Commentary On The Whole Bible

Is a candle brought to be put under a bushel? — See Note on Matthew 5:15. St. Mark, it will be noted, omits all the other parables that follow in St. Matthew, and connects with that of the Sower sayings more or less proverbial, which in St. Matthew appear in a different context. Looking at our Lord’s method of teaching by the repetition of proverbs under different aspects and on different occasions, it is not unlikely that this of the “candle” was actually spoken in the connection in which we find it here. Their knowledge of the meaning of the parable was not given them for themselves alone, but was to shine forth to others. We probably owe to the saying so uttered the record of this parable given in three out of the four Gospels.