“[The kingdom of God] is like a grain of mustard seed, which, when sown on the ground, is the smallest of all the seeds on earth, yet when it is sown it grows up and becomes larger than all the garden plants and puts out large branches, so that the birds of the air can make nests in its shade.” Mark 4:31-32
Though the parables of Jesus were different from those spoken by other Rabbis of His day, yet there were similarities in the use of certain “stock” illustrations in such parables. The following are recognized as some of the stock illustrations found in rabbinic parables in the first century: A king represented God; harvest represented judgment; marriage represented the Messianic Age; a field represented the world; birds represented gentiles or evil beings. Jesus added His own “stock” illustrations, probably the most notable being the sowing of seed, which represented the spread of the Kingdom through preaching.
Unlike other rabbis, Jesus rarely gave interpretations to His parables; He fully expected people to wrestle with them, seeking interpretations consistent with the Old Testament and with what Christ had revealed to His Apostles. Those who rejected the guidance of the Holy Spirit and thus would not wrestle with Christ’s parables, who just brushed them off as practically useless, are those who hearing they do not hear, nor do they understand [Mt 13:13].
An obvious point being made by the parable of the mustard seed, is that Christ’s kingdom will start as a very small seed, but it will ultimately grow into a towering tree. We who can look back on the progress of the Church can clearly see this reality; the Church started so small it seemed ready to perish because of poverty and persecution, but it has since grown to tower over every continent. This has happened not because of clever planning, nor because of shrewd business models, nor because of charismatic church leaders through the centuries, nor because the message has been “adapted” to fit every culture and era. It has happened because the message of the Gospel—the good news of Christ’s saving death and His life-guaranteeing resurrection—continues to change people by the Holy Spirit who works thereby. People are not only thus born anew in Christ Jesus, but simultaneously they are changed and empowered to produce the God-pleasing, Christ-like fruit of love.
This brings us to a secondary point made by the parable. When Christ’s kingdom has thus grown into a monumental tree, its branches are able to provide a place for the birds. In Mark’s record of the parable, the birds nest in the Kingdom’s shade, and in Matthew’s account, the birds nest in the Kingdom’s branches. Christ’s parable thus portrays how the Church is a blessing to the “birds” which rest/nest in its shady branches. As the “birds” were gentiles in rabbinic parables, and as Jesus would use “birds” in another parable to illustrate demons snatching God’s seed, so now in this parable one can readily recognize the “birds” to be the non-Christians of the world. Indeed Christ’s Church is and has been a blessing even to unbelievers! On every continent the Church has become the source of previously unknown wisdom and love. In his book, How Christianity Changed the World, Alvin Schmidt has shown how Christ’s kingdom has been THE positive influence on the world’s charitable attitudes. Before the Church of Christ, there were no hospitals, no adoption agencies and no charities to help the poor and elderly. Christianity has elevated marriage, sexuality and children. It has given women dignity and worth like never before. In summary, Christ’s incarnation, death and resurrection have given heretofore unknown value to fallen people. When Christians—that is, those re-born to be in and like Christ—permeate a godless society, the godless “birds” are unknowingly blessed.
Of course God’s goal is not simply to graciously bestow blessings on unbelievers (“birds”), yet it shows the love of Christ, a love Christians do not withhold from unbelievers. God’s desire is that all people come to the knowledge of the truth—that they also become members of Christ’s body, the Church.