Besides, Scripture anticipated God's justification of the Gentiles by faith when it announced the gospel beforehand to Abraham in these terms: All nations shall be blessed in thee.
but Scripture has consigned all without exception to the custody of sin, in order that the promise due to faith in Jesus Christ might be given to those who have faith.
Now the Promises were made to Abraham and to his offspring; it is not said, 'and to your offsprings' in the plural, but in the singular and to your offspring — which is Christ.
Then the seventh angel blew; and loud voices followed in heaven, crying, "The rule of the world has passed to our Lord and his Christ, and he shall reign for ever and ever."
However, what does the scripture say? Put away the slave-woman and her son, for the son of the slave-woman shall not be heir along with the son of the free-woman.