Romans 4:16

That is why it all turns upon faith; it is to make it a matter of God's favor, so that the promise may hold good for all Abraham's descendants, not only those who are adherents of the Law, but also those who share the faith of Abraham. For he is the father of all of us;

Romans 9:8

That is to say, it is not his physical descendants who are children of God, but his descendants born in fulfilment of the promise who are considered his true posterity.

Romans 15:8

I hold that Christ has become an agent of circumcision to show God's truthfulness in carrying out the promises made to our forefathers,

Galatians 3:22

But the Scripture describes all mankind as the prisoners of sin, so that the promised blessing might on the ground of faith in Jesus Christ be given to those who have faith.

Romans 3:24-26

but by his mercy they are made upright for nothing, by the deliverance secured through Christ Jesus.

Romans 4:11

and he was afterward given the mark of circumcision as the stamp of God's acknowledgment of the uprightness based on faith that was his before he was circumcised, so that he should be the forefather of all who, without being circumcised, have faith and so are credited with uprightness,

Romans 5:1

So as we have been made upright by faith, let us live in peace with God through our Lord Jesus Christ,

Galatians 3:7-12

So you see, the real descendants of Abraham are the men of faith.

Ephesians 2:5

he made us, dead as we were through our offenses, live again with the Christ. It is by his mercy that you have been saved.

Ephesians 2:8

For it is by his mercy that you have been saved through faith. It is not by your own action, it is the gift of God.

Titus 3:7

so that we might be made upright through his mercy and become possessors of eternal life in fulfilment of our hope.

Hebrews 6:13-19

For when God made his promise to Abraham, since there was no one greater for him to make oath by, he did so by himself,

2 Peter 1:10

Therefore, brothers, make all the greater efforts to make God's call and choice of you certain. For if you have these qualities, you will never stumble,

Treasury of Scripture Knowledge

Summary

Therefore it is of faith, that it might be by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all,

But to

The father

Bible References

Of faith

Romans 3:24
but by his mercy they are made upright for nothing, by the deliverance secured through Christ Jesus.
Romans 5:1
So as we have been made upright by faith, let us live in peace with God through our Lord Jesus Christ,
Galatians 3:7
So you see, the real descendants of Abraham are the men of faith.
Ephesians 2:5
he made us, dead as we were through our offenses, live again with the Christ. It is by his mercy that you have been saved.
Titus 3:7
so that we might be made upright through his mercy and become possessors of eternal life in fulfilment of our hope.

The promise

Hebrews 6:13
For when God made his promise to Abraham, since there was no one greater for him to make oath by, he did so by himself,
2 Peter 1:10
Therefore, brothers, make all the greater efforts to make God's call and choice of you certain. For if you have these qualities, you will never stumble,

But to

Romans 4:11
and he was afterward given the mark of circumcision as the stamp of God's acknowledgment of the uprightness based on faith that was his before he was circumcised, so that he should be the forefather of all who, without being circumcised, have faith and so are credited with uprightness,

The father

Romans 9:8
That is to say, it is not his physical descendants who are children of God, but his descendants born in fulfilment of the promise who are considered his true posterity.

General references

Luke 10:26
Jesus said to him, "What does the Law say? How does it read?"
Galatians 3:9
So the men of faith share the blessing of Abraham and his faith.
Galatians 4:28
Now we, brothers, are like Isaac, children born in fulfilment of the promise.