The Fullness of Gentiles in Romans
Apostle Paul’s letter to the Romans is not easy reading. In my opinion, it is written from the perspective of a missionary to non-Jews, who wants them to understand that they are not the axis, but a part of a much bigger ancient plan. In this message, Paul speaks about the fullness of Gentiles and seeks to explain the ontological connection of Roman Christians to the Jewish people. If one reads the letter carefully with this in mind, it becomes obvious how Paul does this in a number of ways throughout the entire epistle.

One of the most pictorial attempts in the core of the book is the imagery of the olive tree with Gentiles being grafted into it, thus becoming a part of something they previously were not. It's a beautiful and easy-to-understand agricultural metaphor. Contrary to their nature, they (Gentiles) were grafted into the cultivated olive tree among Jews because of their belief in the God of Israel. Paul calls this a mystery and tries to explain how this is possible.
For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fullness of the Gentiles be come in. (Rom. 11:25 KJV)
The preposition “until” gives one the impression that Israel’s blindness to Yeshua (Jesus) is temporary. Somehow, the fullness of Gentiles will bring this period of unbelief to its expiration. The blindness, by the way, in this context is Israel’s inability to see the “good news” (Rom. 11:28) and according to Paul, it was divinely initiated for the sake of non-Jews (Rom 11:30-32). So, what does Paul mean when he uses this phrase πλήρωμα τῶν ἐθνῶν (pleroma ton ethnon), – the fullness of Gentiles in Rom. 11:25? Because of this unclear terminology, this verse is one of those “tough” passages that can be understood in a number of ways, and indeed, interpretations abound.
The word πλήρωμα (pleroma) – fullness is very broad when it appears by itself (just like in English). To mind comes a passage from the Torah that speaks about “the fullness of the sin of Amorites” (Gen. 15:16). God gave opportunities to Canaanites to repent, waiting for their sin to reach the limit, and then the Israelites were allowed to take over their land. In the New Testament, one reads about the fullness of the time of Gentiles (Luke 21:23). The passage resonates with the prophets of Israel, predicting the rule of the Gentiles over Israel. But that rule comes to a conclusion as well, ending the times of the Gentile domination of Israel.
