The “sons of Israel,” in Rev. 7:4-8, applies to all of God's baptized people, as you note. This does not refer just to natural Israel for Paul explains that there is "no distinction between Jew and Greek, for there is the same Lord over all." (Rom. 10:12) The number [144,000] of those who are sealed out of the sons of Israel refers to the "Israel of God." (Gal. 6:16) These are the "holy ones" that the prophet Daniel speaks of who share in the rulership in the kingdom received by the "son of man." (Dan. 7:13,14, 18, 21,22, 27; Rev. 3:21) Thus, Jesus promised his twelve disciples that "when the Son of man sits down upon his glorious throne, you who have followed me will also yourselves sit upon twelve thrones, judging the twelve tribes of Israel." (Matt. 19:28)

At Pentecost the twelve apostles and 108 other disciples were the first to be sealed out of "the sons of Israel," at that time still natural Israel, for although the new covenant came into existence on that occasion, Jehovah had promised to keep his covenant toward his people Israel in force "for one week." (Dan. 9:26,27) The "week" (week of years = seven years) began with the anointing of the Messiah, when Jesus was baptized. "At the half of the week" (three and a half years) Jesus was put to death or "cut off," and "sacrifice and gift offerings" ceased, bringing to an end God's acceptance of the sacrifices offered at the altar according to the Mosaic law. The last half of the "week" continued for another three and a half years and ended when the first Gentile, Cornelius, was anointed and sealed with holy spirit. Thus came to an end the special status and privileges according to the old covenant and any distinction between Jews and non-Jews. From then on the choosing and sealing of the 144,000 has continued from among all of God's people, and continues right into the time of the end and the "conclusion of the system of things." (Acts 10:34-48; Dan. 12:4; Matt. 28:20; Rev. 7:1-3)

You said: “We know that these ‘sons of Israel’ don't refer to fleshly Israel but spiritual Israel.” Actually, the expression "spiritual" Israel does not appear anywhere in the Bible, and the term can be misleading, as the Society demonstrates in the way it so liberally uses it. From the very beginning Jehovah purposed to make possible the release from sin and death for all mankind, for every single individual of Adam's offspring. (1 Cor. 15:22) That is what it is all about. That is the theme of the Bible: "from paradise lost to paradise regained!" (Gen. 3:15; Isa. 65:17-25; Rev. 21:2,-4) We get confused in the details on how Jehovah was going about fulfilling this. Let me explain:

God's covenant with Abraham guaranteed that the promised seed of Genesis 3:15 would come through Abraham's line of descent. "And by means of your seed all nations of the earth will certainly bless themselves." (Gen. 22:18; 26:4) God kept his promise, as Paul notes: “Now the promises were spoken to Abraham and to his seed. It says, not: ‘And to seeds,’ as in the case of many such, but as in the case of one: ‘And to your seed,’ who is Christ.” (Gal. 3:16)

The promise to Abraham produced the nation of Israel, through whom God fulfilled his original promise of raising a seed who would "break up the works of the Devil." (1 John 3:8) That means that once the promised seed, Christ Jesus, arrived and the ransom was paid for all mankind, then there would no longer be any distinction between a Jew and a person of the nations, as they would all have equal standing before God. From then on it no longer mattered what a person was by birth. (Rom. 3:29) For that reason Jehovah brought about the new covenant, which replaced the old covenant that he had entered into exclusively with the nation of Israel. (Deut. 7:6, 12; Jer. 31:31-34) In fact, everything about the old covenant was in preparation of the new one. (Col. 2:17; Heb. 9:15-24; 10:1) Jesus is the mediator of this new covenant and it includes everyone who exercises faith in him, yes, people of all nations. (1 Tim. 2:5,6; Heb. 8:6-13) This part of God's purpose had nothing to do with whether the nation of Israel would prove faithful or not.

In view of this, Paul rightly asks: "What, then, is the superiority of the Jew?" (Rom. 3:1) A great deal, as he explains in his book to the Romans, for it was the nation of Israel that Jehovah used to write the Bible. And through them he not only produced the promised Messiah, Jesus Christ, but also 144,000 "bought from among mankind as firstfruits to God." (Ex. 19:5,6; Rev. 14:1-4; 20:6) These are the ones the Bible calls the “Israel of God," for whereas the Jews as a nation would eventually lose their identity as being Israelites (especially under God's kingdom), this "little flock" will always keep their uniqueness of belonging to "Israel," in keeping with God's promise to Abraham. (Luke 12:32)

The apostle Paul explains at great length that Jehovah did not abandon his promise to Abraham by grafting wild (gentile) branches into the domestic tree (representing the "Israel of God") because of the lack of faith of the natural Jews. Grafting wild branches into the garden tree did not alter the tree, as if making it a different tree. It is still the same tree, for "if the root is holy, the branches are also." (Rom. 11:13-26) That is why Paul notes: "Surely you know that those who adhere to faith are the ones who are sons of Abraham." "For not all who spring from Israel are really 'Israel.' Neither because they are Abraham's seed are they all children." (Gal. 3:7; Rom. 9:6,7) It is by the grafting in of foreign branches into the domestic tree that the full number of the 144,000 will be filled, and as Paul puts it, "and in this manner all Israel will be saved." (Rom. 11:26) This is the "kingdom of priests and a holy nation" that Jehovah talked of at the time of making the covenant at Mount Sinai. It never referred to the entire nation of Israel. (Ex. 19:5,6)

You can readily see that the "Israel of God" is real, genuine, as real as God's kingdom itself. It is not merely a "spiritual" Israel, as if God’s kingdom were merely a spiritual kingdom! And it certainly has not replaced natural Israel in God's purpose, as some Watchtower articles have claimed. Natural Israel was used by God to fulfill his purpose. It was not replaced, and neither did Jehovah ever purpose to do so. Even if the natural Jews had proved faithful and not had been rejected as a nation, they still would have been united with all mankind, families of all the nations, in worshiping Jehovah just as it had been foretold. (see Psalms 22:27,28) After all, that was what God's covenant with Abraham was all about, namely, "by means of your seed all nations of the earth will certainly bless themselves." The only replacing that took place, as already noted, was the grafting in of wild branches into the symbolic Israel of God tree. Jehovah has been choosing these replacement branches from among all his people, who are prophetically referred to as the twelve tribes of Israel, because just as his people ancient Israel were in a covenant with him, so also all his worshipers today are in the new covenant. These are the ones who are not chosen, but rather look forward to the joy of living forever on a paradise earth, the original prospect that had been put before Adam, but who threw it away for himself and any of his offspring who likewise refuse to obey Jehovah.

And as you rightly conclude, all of God's people are instructed by Jesus to “keep doing this in remembrance of me,” and "partake of the symbolic bread and wine" at the Memorial. (Luke 22:14-20) Not only is there no scriptural prohibition not to partake, or perhaps limiting it to only a few, but there is solid scriptural evidence that everyone is included. You may remember a few weeks ago in our Bible reading in the book of Numbers, that Jehovah's law to the Israelites regarding the Passover celebration (which the Memorial has replaced) included this command: "And in case an alien resident should be residing with you as an alien, he also must prepare the passover sacrifice to Jehovah. According to the statute of the passover and according to its regular procedure is the way he should do. There should exist one statute for you people, both for the alien resident and for the native of the land." (Num. 9:14) Is it not Jehovah’s view on the matter that is important, even when it differs with our own traditions? (Matt. 15:6-9)

Our present tradition regarding how we celebrate the Memorial of Jesus Christ dates back to Rutherford's days (just like many of our other doctrines), when he identified the "great multitude" of Revelation as survivors of Armageddon who will live on earth, and whom he dubbed the modern-day "Jonadabs." These were considered inferior to "spiritual" Israel. In fact, they were not even considered to be Jehovah's Witnesses between 1934 to 1942 (see "Proclaimers" book, page 83, footnote). Some understandings in regard to the "great multitude” has changed since then as new light, such as dropping the term “Jonadabs” in favor of “other sheep;” and acknowledging that they too have God’s spirit yet never considering them as equals to the “spiritual” Israel, namely themselves, for these so-called “other sheep” of worshipers are said to be privileged to associate with them. These ones are strongly discouraged (actually forbidden) from partaking at the Memorial, for it is still claimed that they are not in the new covenant and neither is Jesus their mediator.

And, by the way, the great crowd, "which no man was able to number, out of all nations and tribes and peoples and tongues," is not a class of people, but rather simply refers to the undetermined number of survivors of the great tribulation who had "washed their robes and made them white in the blood of the Lamb," in contrast to the definite number of the "Israel of God."─Rev. 7:9,10, 14.

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