William Burkitt on Romans 11:25

Here the apostle fully proves, that the rejection of the Jews was neither total nor final; not total, because blindness in part only, happened unto Israel; that is, part of the Jews only are left in unbelief, and under the power of spiritual blindness. Nor is their rejection final, but for a time only; namely, till the fulness of the Gentiles be come in: that is, till the Gentile churches be advanced to an honourable state and fulness. And then all the Israel of God, the faithful seed of Abraham, and the main body of the Jews, shall make up the catholic church, and be saved from their unbelief; according to that gracious promise, The Redeemer shall come to Zion, and unto them that turn from transgression in Jacob: and this is my covenant with them, My Spirit shall not depart from thy seed, nor thy seed's seed, from henceforth and forever. Isa 59:20,21.

Learn hence, That there shall be a general calling of the Jews to the faith of the gospel before Christ's second coming, is not only possible and probable, but infallible, sure, and certain, and that from the prophecies and predictions of the prophets of God; let us therefore believe it firmly, pray for it fervently, and live in the expectation of it continually.