Do ye look at things according to the outward appearance? If any one is confident in himself that he is Christ's, let him consider this again of himself, that as he is Christ's, so we also are Christ's.

Abraham's

so ye know that they who believe, are the children of Abraham.

where it is written, that Abraham had two sons, one by a servant, and one by a free-woman?

and the father of circumcision to those, who not only are of the circumcision, but also walk in the steps of that faith of our father Abraham, which he had in uncircumcision.

Nor because they are the seed of Abraham, are they all children of promise: but "in Isaac shall thy seed be called."

of whom it was told him, that in Isaac shall thy seed be called:

Heirs

So that thou art no longer a servant, but a son; and if a son, an heir also of God through Christ.

For the promise made to Abraham, or to his seed, that he should be heir of the world, was not by the law, but by the righteousness of faith:

And if children, then heirs; heirs of God, and co-heirs with Christ: if so be we suffer with Him, that we may be also glorified with Him.

whether Paul, or Apollos, or Cephas, or the world, or life, or death, or things present, or future, all are yours;

and of the same body, and joint-partakers of his promise in Christ, by the gospel:

that being justified by his grace, we might become heirs according to the hope of eternal life.

Are they not all ministring spirits, sent forth to attend on those who shall be heirs of salvation?

Wherefore God being willing more abundantly to manifest unto the heirs of the promise the immutability of his counsel, confirmed it with an oath:

By faith Noah being warned by God of things which were not yet seen, moved with pious fear, prepared an ark for the safety of his family; whereby he condemned the world, and became heir of the righteousness which is by faith.

Hear, my beloved brethren; hath not God chosen the poor of this world who are rich in faith, and heirs of the kingdom, which He hath promised to them that love Him? but ye have slighted the poor.

He that overcometh shall inherit all things, and I will be a God to him, and he shall be to me a son.

General references

or is He the God of the Jews only, and not also of the Gentiles?

So then they that believe, are blessed with believing Abraham.

Now we, brethren, like Isaac, are children of the promise.