The picture of a plant taking root is used in the Bible to teach us the idea of conversion. When someone's heart is turned from himself and his sinful ways to faith in Jesus and devotion to God, it is like a plant which starts to shoot out roots into rich soil so that it can live and take nourishment. There is no way for a plant to have life unless it takes root, and there is no way for a person to have spiritual life unless God turns him or her out of the way of death and into the way of life.