Author Don Schwager, Servants of the Word - Matthew 13:31-35 - Another parable he put before them, saying, "The kingdom of heaven is like a grain of mustard seed which a man took and sowed in his field; it is the smallest of all seeds, but when it has grown it is the greatest of shrubs and becomes a tree, so that the birds of the air come and make nests in its branches." He told them another parable. ...