Again, the kingdom of heaven is like unto a merchant man, seeking goodly pearls: Who, when he had found one pearl of great price, went and sold all that he had, and bought it. Mat 13:45-46 KJV
The kingdom of Heaven, is “like” a pearl, thus the “realm of profession,” which should always be understood in connection with things on Earth. The mystery of the kingdom of Heaven here is that of the true Church. The parable of the treasure exemplifies Israel in relation to the kingdom of Heaven. In that parable Israel is pictured with an earthly calling and hid in the world so that it had to be bought in order to get the treasure, but in this parable the pearl is bought without buying the world, for the calling of the Church is heavenly. The sons of God (the wheat) are the true children of the kingdom and make the present Church, but the sons of the devil (the tares), who profess to be children of the kingdom, are also in the “sphere of profession,” endeavoring to counteract God’s purpose in the kingdom. This parable emphasizes the fact that the Church is not the kingdom of Heaven. It is only a part of the kingdom of Heaven.
The man illustrates Christ, as in all the preceding parables. Mt. 13:3, 24, 37, 44 and the pearl illustrates the true Church that Christ gave all for in order to buy it and redeem it to Himself. Eph. 5:25-31 The great price illustrates the treasure of Heaven that God had to give in order to get the human race redeemed from the devil. Jn. 3:16; 6:51; 10:11, 18; 19:30; 1 Cor. 6:20; 1 Pet. 2:24; Rev. 5:6, 9; 12:11 Pearls are sometimes formed by the introduction of a foreign body, possibly a grain of sand, into the muscular structure of an oyster, which secretes a substance about the sand, layer after layer, until a beautiful pearl is formed. This is a wonderful picture of the gradual formation of the body of Christ. 1 Cor. 10:17; 12:12-28; Eph. 2:14-22; 4:11-16; 5:25-31
For we being many are one bread, and one body: for we are all partakers of that one bread. 1Cor. 10:17 KJV