Galatians 4:1

Now I say that so long as an heir is a child, he in no respect differs from a slave, although he is the owner of everything,

Galatians 4:23

But we see that the child of the slave-girl was born in the common course of nature; but the child of the free woman in fulfilment of the promise.

Galatians 4:29

Yet just as, at that time, the child born in the common course of nature persecuted the one whose birth was due to the power of the Spirit, so it is now.

Treasury of Scripture Knowledge

Summary

Now I say, That the heir, as long as he is a child, differeth nothing from a servant, though he be lord of all;

Bible References

That

Galatians 4:23
But we see that the child of the slave-girl was born in the common course of nature; but the child of the free woman in fulfilment of the promise.