After the birth, there is the need of growth. Verse 8 says that "the child grew, and was weaned: and Abraham made a great feast the same day that Isaac was weaned." It is not sufficient simply to bring Christ forth. The very Christ whom we have brought forth must grow. In the past few years, many of us have brought forth Christ, but I wonder whether this Christ has grown up. Has there been the time of weaning? Isaac grew up and was weaned away from his mother's nourishment, meaning that he was no longer a young child but had become a young boy. On the day of his weaning, Abraham made a great feast. We can understand the significance of this according to our experience. When in the church life we see that Christ has grown up in certain brothers and sisters, we all will be happy and have a great feast, a great enjoyment.
It is not easy to have either the birth of Isaac or his growth. Likewise, it is not easy to have Christ brought forth, nor to have Him grown up. In the church life we need to have both the bringing forth and the growth of Christ. I thank God that Christ has been brought forth among us, but I hesitate to say that we have had much of the growth of Christ. It is wonderful to see that Christ has been brought forth in a particular young brother, but we are still waiting to see in him the growth of Christ. We want to see that the Christ in him has been weaned and is no longer a baby. Although the Christ in that brother may not yet be a full-grown man, we want to see Him as a strong boy. Christ must be formed not only in us but also among us (Gal. 4:19). In both our daily life and the church life we need the expression of a formed Christ. Then we may have a great feast for the enjoyment of God's grace.
According to Genesis 21, it was not the birth of Isaac that stirred up trouble; it was his growth. When Isaac was born, Hagar and her son Ishmael were not bothered very much. But after Isaac had grown up, Ishmael began to mock him (v. 9). In the biblical sense, this means that Ishmael was persecuting Isaac. God even counted Ishmael's persecution of Isaac as the beginning of the four-hundred-year persecution of His people (15:13; Acts 7:6). Ishmael's mocking was a serious thing because Isaac was God's ordained seed and Ishmael was the counterfeit. The counterfeit always hates the ordained. We, the ordained seed, are hated by the counterfeit. As Paul says in Galatians 4:29, "But as then he that was born according to flesh persecuted him that was born according to Spirit, so also it is now." The growth of Isaac stirred up that persecution.