when we become born again, aren't we adopted into the jewish bloodline?

there is neither man, woman, jew or gentile in the body of Christ

Well, no, not really. We are grafted into the vine as a "wild" olive branch. The Jewish line is just that, the Jewish line. The church is totally different thing. If we don't come to terms with this, prophetic passages will become confusing. Read my study below to see the role of the church. Israel is the clock, the church is the hinderance pin that stops the clock--for a while at least.

What grafted-in means

“But I am speaking to you who are Gentiles. Inasmuch then as I am an apostle of Gentiles, I magnify my ministry… But if some of the branches were broken off, and you, being a wild olive, were grafted in among them and became partaker with them of the rich root of the olive tree, do not be arrogant toward the branches; but if you are arrogant, remember that it is not you who supports the root, but the root supports you.” – Romans 11:13, 17, 18, NASB

A wonderful truth is being revealed here. What does it mean for Paul ... to say that the ‘wild olive branch’ is grafted into the ‘cultivated olive tree’?  The plain sense of the text is not easily confused:

• Through the efficacious ministry of the Messiah Yeshua, Gentile believers (wild olives) are covenant–bound (grafted in) to Isra'el (Father Abraham’s Olive Tree). Therefore Gentile believers are fellow citizens and full-participants with the Commonwealth of Isra'el (Eph. 2) and are granted the divine privilege of following the entire Torah.

• We believe that God has written this very same Torah upon every heart, Jew and Gentile, of those who have placed their trusting faithfulness in Yeshua (Jer. 31:31-34; Heb. 8:7-12).

• We believe that this same Torah is a foundational revelation of the righteousness of God and serves as a description, along with the rest of the Scriptures, of the lifestyle of the Redeemed Community (James 1:16-27).

• Furthermore, the words ‘Grafted In’ memorialize the affirmation of our true identity as a people, Jew and Gentile, securely rooted in the finished work of Yeshua HaMashiach.

If you believe in Yeshua, you are Grafted In!

Most Christian churches wouldn't agree with that (although there are just a few!). "Bloodline" is too anatomical ... theologians usually refer to a "salvation history," through which God acts in the world in increasingly more direct ways.

I think it would be more appropriate to say that "born again" Christians become part of the STORY of God's action in the world, which encompasses Judaism and Christianity (and many other religions as well).

Perhaps "cousins" fits the relationship.

Jesus Himself got angry at the Jews who were trying to force the new Gentile Christians into performing Jewish customs (circumcision, food restrictions, etc.) Jesus being as Jewish as they came, certainly wouldn't have been upset with them if they were doing what He wanted. So no! We are set free in Christ. Not confined to the old law.

There is nothing in the Old Testament that talks about being born again, hence it is not a jewish concept, at least on its face. There is no direct mention of Jesus there either.

Of course you can twist any phrase in any book to your needs, but I am talking about what the book says, not what you think it means. I can't address that.

The early church restled with this question. The Apostle Paul won the argument, you do not have to become Jewish to become a Christian.

The Jews are God's chosen people. The bible states that.Jews also were some of the first early christians. In heaven, we all ,jews and christians, will be with Jesus and God in Heaven worshipping God.

No, we become God's bloodline! You know that bloodline that was spilt for out sins!

no, they were God`s chosen ppl, but after we become christians we dont automaticly become jews.