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Stephen was Jewish!
The first Church consisted of Jews!
Acts 6 reveals that context!
Acts 6:8-12
Now Stephen, a man full of God’s grace and power, performed great wonders and signs among the people.
Opposition arose, however, from members of the Synagogue of the Freedmen (as it was called)—Jews of
Cyrene and Alexandria as well as the provinces of Cilicia and Asia—who began to argue with Stephen.
But they could not stand up against the wisdom the Spirit gave him as he spoke.
Then they secretly persuaded some men to say, “We have heard Stephen speak blasphemous words against
Moses and against God.”
So they stirred up the people and the elders and the teachers of the law. They seized Stephen and brought him
before the Sanhedrin.
JEWISH! That was the audience Stephen was addressing!
In contrast to gentile believers..
Israel came from not only Abraham's seed.
But to be Israel one must be from the literal seed that included Isaac and Jacob!
But?
The Gentiles are of a different nature.
Not Israel.
But, Gentile Abraham’s seed!
The gentiles became the spiritual offspring of what Abraham was like when he first became a believer.
Abraham was a gentile!
The gentiles were following Abraham's example.
So, they are gentiles (just as Abraham was a gentile) when Abraham believed.
Gentiles who believe have become a type of spiritual offspring of gentile Abraham's model.
That does not mean gentiles have become Israel.
To do that?
It would require that they also have been of the seed of Isaac and Jacob!