The promises were spoken to Abraham and to his seed. The Scripture does not say, “and to seeds,” meaning many, but “and to your seed,” meaning One, who is Christ.
KJV
Now to Abraham and his seed were the promises made. He saith not, And to seeds, as of many; but as of one, And to thy seed, which is Christ.
ASV
Now to Abraham were the promises spoken, and to his seed. He saith not, And to seeds, as of many; but as of one, And to thy seed, which is Christ.