Gen.2:17 says nothing about having eternal life. You are assuming Adam had eternal life.
NT understanding of man's immortal spirit is grounded in
Ge 2:17.
Adam lost
two kinds of life there, "
Dying, you shall
die." (Check out this translation with someone who knows Hebrew).
The first was God's divine
eternal life imparted to his spirit, the second was
physical life later on.
That's the reason for
1) the NT "re-birth" of
Jn 3:3 -- from spiritual
death (absence of God's eternal divine life)
back to spiritual
life (re-impartation of God's eternal divine life) to the immortal human spirit, which life Adam lost, as he did physical life.
2) the resurrection -- restoration from physical
death back to physical
immortality (
1 Co 15:53), which immortality Adam lost, as he did spiritual life (God's eternal divine life imparted to the immortal human spirit).
We don't see the same thing in salvation (assuming I'm understanding you correctly). The Church was unheard of prior to the Cross
Yes. . .and no.
In
Ac 7:38, Israel is called the assembly (
ekkelsia; i.e., church) in the wilderness/desert.
The meaning of
ek-klesia (church) is "called-out assembly."
and what we have been given is far superior to what was promised any OT saint. For example, Israel was promised a Messiah to rule over them. We (the Church) have been made a bride to rule with her Husband the Lord Jesus Christ. Not all believers inherit the same promises.
There is no basis in NT apostolic teaching for more than
one group of God's people, the
one olive tree of God's people (
Ro 11:17-23), going all the way back to Abraham (
Ro 11:16), and into which it is Israel's destiny to be
grafted back IF (not "when") they do not persist in unbelief (
Ro 11:23).
Both Gentiles and Jews are part of the
one people of God, the
church.
God's gifts and irrevocable call (
Ro 11:29) to Israel are being fulfilled in a remnant now (
Ro 11:1-5), just as it is with the Gentiles.
Israel is on the same footing as the Gentiles, salvation is by faith in Jesus Christ. . .and God is saving a remnant of both.