And again he said, Whereunto shall I liken the kingdom of God? It is like leaven, which a woman took and hid in three measures of meal, till the whole was leavened. Luke 13:20, 21. YRP 18.1
This parable illustrates the penetrating and assimilating power of the gospel, which is to fashion the church after the divine similitude by working on the hearts of the individual members. As the leaven operates on the meal, so the Holy Spirit operates on the human heart, absorbing all its capabilities and powers, bringing soul, body, and spirit into conformity to Christ. YRP 18.2
In the parable the woman placed the leaven in the meal. It was necessary to supply a want. By this God would teach us that, of himself, man does not possess the properties of salvation. He cannot transform himself by the exercise of his will. The truth must be received into the heart. Thus the divine leaven does its work. By its transforming, vitalizing power it produces a change in the heart. New thoughts, new feelings, new purposes are awakened. The mind is changed, the faculties are set to work. Man is not supplied with new faculties, but the faculties he has are sanctified. The conscience hitherto dead is aroused. But man cannot make this change himself. It can be made only by the Holy Spirit. All who would be saved, high or low, rich or poor, must submit to the working of this power. YRP 18.3
This truth is presented in Christ's words to Nicodemus: “Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God.... That which is born of the flesh is flesh; and that which is born of the Spirit is spirit. Marvel not that I said unto thee, Ye must be born again. The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh, and whither it goeth: so is every one that is born of the Spirit” (John 3:3-8). YRP 18.4
When our minds are controlled by the Spirit of God, we shall understand the lesson taught by the parable of the leaven. Those who open their hearts to receive the truth will realize that the Word of God is the great instrumentality in the transformation of character.—The Review and Herald, July 25, 1899. YRP 18.5