Galatians 4:1

What I mean is this. As long as the heir is a child, he differs in no respect from a slave, though he be the owner of the whole inheritance;

Galatians 4:23

but while the son by the slave woman was born according to the flesh, the son by the free woman was born in fulfilment of a promise.

Galatians 4:29

but just as in old times the son born by the flesh used to persecute the son born by the power of the Spirit, so also 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 while the son by the slave woman was born according to the flesh, the son by the free woman was born in fulfilment of a promise.