The great 19th century theologian and Anglican Bishop John Charles Ryle issued a simple challenge that has never been satisfactorily answered. Below is the question in bold and the context in which it is found:
The word ‘Israel’ is used nearly seven hundred times in the Bible. I can only discover three senses in which it is used. First, it is one of the names of Jacob, the father of the twelve tribes; a name specially given to him by God. Secondly, it is a name given to the ten tribes which separated from Judah and Benjamin in the days of Rehoboam, and became a distinct kingdom. This kingdom is often called Israel in contradistinction to the kingdom of Judah. Thirdly and lastly, it is a name given to the whole Jewish nation, to all members of the twelve tribes which sprung from Jacob, and were brought out of Egypt into the land of Canaan. This is by far the most common signification of the word in the Bible. It is the only signification in which I can find the word ‘Israel’ used throughout the whole New Testament … What I protest against is, the habit of allegorising plain sayings of the Word of God concerning the future history of the nation Israel, and explaining away the fullness of their contents in order to accommodate them to the Gentile Church. I believe the habit to be unwarranted by anything in Scripture, and to draw after it a long train of evil consequences. Where, I would venture to ask, in the whole New Testament, shall we find any plain authority for applying the word ‘Israel’ to anyone but the nation Israel? I can find none. On the contrary, I observe that when the Apostle Paul quotes Old Testament prophecies about the privileges of the Gentiles in gospel times, he is careful to quote texts which specifically mention the ‘Gentiles’ by name. The fifteenth chapter of the Epistle to the Romans is a striking illustration of what I mean. We are often told in the New Testament that, under the gospel, believing Gentiles are ‘fellow heirs and partakers of the same hope’ with believing Jews (Eph. 3:6). But that believing Gentiles may be called ‘Israelites’, I cannot see anywhere at all.
Ryle seems to have overlooked Messiah being referred to as Israel in Isaiah 49:3. Messiah is Israel in that He represents the Israelites in fulfilling God’s expectations and is a light to the Gentile nations (Is. 49:6). This point is only even mentioned out of intellectual honesty and it hardly undermines Ryle’s message.
What New Testament verses may we turn to in attempting to answer Ryle’s challenge? Perhaps Romans 9:6 will do? The verse reads:
But it is not as though the word of God has failed. For not all who are descended from Israel belong to Israel. (ESV)
If one is given to reading this verse removed from those surrounding it and with presuppositions then it could be taken to mean that this latter Israel includes Gentiles. Though there is nothing in the Text that would allow for this rather significant leap. The latter Israel refers to Israelites who were not only Jews outwardly with an outward circumcision but inwardly as well with a circumcision of the heart (Rom. 2:28-29).
What about all Israel in Romans 11:26? The problem with this example is that the previous verse makes a clear distinction between Israel and the Gentiles. This distinction should not exist if Israel is meant to include the Gentiles. The phrase all Israel is then referring to the Jews to be saved after the fullness of the Gentiles has come in (Zech. 12:10-14; Rom. 11:25).
Surely though the reliable Israel of God found in Galatians 6:16 is enough to silence Ryle? Let us examine the verse to be certain:
And as for all who walk by this rule, peace and mercy be upon them, and upon the Israel of God.
The rule is to be a new creation in Jesus Christ and not whether one is circumcised (Gal. 3:14-15). Therefore, those who walk by this rule here are all saved Galatians. In addition to them there is the Israel of God. The very use of kai (and) above indicates a differentiation between groups. The Israel of God cannot refer to the Body of Christ as a whole or it would not be spoken as being in addition to.
In writing his epistle to the Galatians, Paul was addressing the problem of certain Judaizers who were teaching that obedience to some of the Mosaic laws were necessary for salvation (notably circumcision). Galatians 6:12-13 is a good example of this and speaks of Judaizers who did not even keep the law themselves. They are hypocrites promoting a gospel of works and thus one different from the authentic (Gal. 1:6-7). In light of the narrative concerning Jews who did not know God, it is easy to understand what the Israel of God refers to: Jews who did know God. Galatians 6:16 also fails to answer Ryle’s challenge.
The verses that I looked to simply could not rise to meet the challenge. Perhaps there are others? Is J.C. Ryle mistaken? Can even one example of Israel found in the New Testament be applied to anything other than the nation Israel? Like Ryle, I can think of none.
 J.C. Ryle, Coming Events and Present Duties: Being Sermons on Prophetical Studies (Whitefish, MT: Kessinger Publishing, 2007), 125–127.