Sorry, but you appear to have a ways to go in your Biblical understanding, because your general theory about the Jews is slanted towards man's social thinking, and not according to God's Holy Writ. Didn't you ever read Judges 2 and 3? and Joshua 9? and Jude 1 about the crept in unawares? God told the children of Israel to literally wipe out the specific nations in the lands of Canaan per Deuteronomy 20. Israel failed, and allowed some of the Canaanites to dwell among them. So God said He would leave those foreigners among Israel to test Israel with. All throughout Israel's history in Old Testament times, those crept in unawares among them were as thorns in their side. The first example of it after God led Israel out of Egypt was indeed when Moses up on the Mount, and the children of Israel below made pagan calf idols in false worship. Who do you think among them led them to do that? So did that mean the children of Israel stopped being the chosen of God? Of course not, even though it made Him very angry, and many of them paid for the sin with their lives later in the wilderness. Or maybe you forget the reason why God made the children of Israel roam in the wilderness for 40 years! (to end that generation that sinned with the idols).
In every OT case, there has ALWAYS been a 'remnant' of the seed of Israel which God preserved unto Himself. Apostle Paul even tells us this plainly in Romans 11 about the remnant of Israel according to the election of grace. God's Church has continued into The New Covenant under Jesus Christ, and that is what you need to remember, instead of the socialist thinking you're being taught instead.
Another thing you should learn, is the difference between the terms "house of Judah" and "house of Israel" per God's Word. The ten lost tribes of Israel represent the "house of Israel" and were never known as Jews. The title of Jew originated from the sole tribe of Judah. At the 1 Kings 11 split of old Israel, the tribes of Judah, Benjamin, and Levi became the Jews living at Jerusalem/Judea.
Thus The GOD of Israel most definitely IS... The same GOD of those in Christ Jesus. And if you had studied Zechariah 12, and the parable about Blessed are the barren... in Luke 23 and Isaiah 54, and then understand in Romans 11 about the blindness Apostle Paul said God put upon the Jews so The Gospel would go to the Gentiles, and that that blindness will one day be removed from them, then you might understand how YHVH and His Son Jesus Christ is still... their God, and our God.
The pre-incarnate Jesus is my God and all he requires from his children is the sacrifice of our heart. I follow Jehovah, not YHVH beware of the subtleties of the imposter. This is what the true God; Jesus the Word, says about sacrifice : -
Isa_1:11 To what purpose is the multitude of your sacrifices unto me? saith the LORD: I am full of the burnt offerings of rams, and the fat of fed beasts; and I delight not in the blood of bullocks, or of lambs, or of he goats.
Isaiah 1:13 Bring no more vain offerings; incense is an abomination to me. New moon and Sabbath and the calling of convocations— cannot endure iniquity and solemn assembly.
1Sa 15:22 "Tell me," Samuel said (to Saul). "Does the LORD really want sacrifices and offerings? No! He doesn't want your sacrifices. He wants you to obey him.
Psa 40:5-6 You have multiplied, O LORD my God, your wondrous deeds and your thoughts toward us; none can compare with you! I will proclaim and tell of them, yet they are more than can be told. In sacrifice and offering you have not delighted, but you have given me an open ear. [Use it.] Burnt offering and sin offering you have not required.
Jer_6:20 To what purpose cometh there to me incense from Sheba, and the sweet cane from a far country? your burnt offerings are not acceptable, nor your sacrifices sweet unto me.
Hos_6:6 For I desired mercy, and not sacrifice; and the knowledge of God more than burnt offerings.
Amo_5:22 Though ye offer me burnt offerings and your meat offerings, I will not accept them: neither will I regard the peace offerings of your fat beasts.
Mic_6:6 Wherewith shall I come before the LORD, and bow myself before the high God? shall I come before him with burnt offerings, with calves of a year old?
Mar_12:33 And to love him with all the heart, and with all the understanding, and with all the soul, and with all the strength, and to love his neighbour as himself, is more than all whole burnt offerings and sacrifices.
Heb_10:6 In burnt offerings and sacrifices for sin thou hast had no pleasure.
Heb_10:8 Above when he said, Sacrifice and offering and burnt offerings and offering for sin thou wouldest not, neither hadst pleasure therein; which are offered by the law;
The practice of making burnt offerings and sacrifice is a pagan custom. There are far too many scriptures to post them all.
Gen_8:20 And Noah builded an altar unto the LORD; and took of every clean beast, and of every clean fowl, and offered burnt offerings on the altar.
Exo_10:25 And Moses said, Thou must give us also sacrifices and burnt offerings, that we may sacrifice unto the LORD our God.
Exo_20:24 An altar of earth thou shalt make unto me, and shalt sacrifice thereon thy burnt offerings, and thy peace offerings, thy sheep, and thine oxen: in all places where I record my name I will come unto thee, and I will bless thee.
Exo_24:5 And he sent young men of the children of Israel, which offered burnt offerings, and sacrificed peace offerings of oxen unto the LORD.
Exo_32:6 And they rose up early on the morrow, and offered burnt offerings, and brought peace offerings; and the people sat down to eat and to drink, and rose up to play.
Lev_4:10 As it was taken off from the bullock of the sacrifice of peace offerings: and the priest shall burn them upon the altar of the burnt offering.
Lev_6:12 And the fire upon the altar shall be burning in it; it shall not be put out: and the priest shall burn wood on it every morning, and lay the burnt offering in order upon it; and he shall burn thereon the fat of the peace offerings.
Lev_7:37 This is the law of the burnt offering, of the meat offering, and of the sin offering, and of the trespass offering, and of the consecrations, and of the sacrifice of the peace offerings;
Lev_9:22 And Aaron lifted up his hand toward the people, and blessed them, and came down from offering of the sin offering, and the burnt offering, and peace offerings.
Lev_22:18 Speak unto Aaron, and to his sons, and unto all the children of Israel, and say unto them, Whatsoever he be of the house of Israel, or of the strangers in Israel, that will offer his oblation for all his vows, and for all his freewill offerings, which they will offer unto the LORD for a burnt offering;
Lev_23:18 And ye shall offer with the bread seven lambs without blemish of the first year, and one young bullock, and two rams: they shall be for a burnt offering unto the LORD, with their meat offering, and their drink offerings, even an offering made by fire, of sweet savour unto the LORD.
Lev_23:37 These are the feasts of the LORD, which ye shall proclaim to be holy convocations, to offer an offering made by fire unto the LORD, a burnt offering, and a meat offering, a sacrifice, and drink offerings, every thing upon his day:
Num_6:14 And he shall offer his offering unto the LORD, one he lamb of the first year without blemish for a burnt offering, and one ewe lamb of the first year without blemish for a sin offering, and one ram without blemish for peace offerings,
Num_10:10 Also in the day of your gladness, and in your solemn days, and in the beginnings of your months, ye shall blow with the trumpets over your burnt offerings, and over the sacrifices of your peace offerings; that they may be to you for a memorial before your God: I am the LORD your God.
Num_15:8 And when thou preparest a bullock for a burnt offering, or for a sacrifice in performing a vow, or peace offerings unto the LORD:
Num_28:14 And their drink offerings shall be half an hin of wine unto a bullock, and the third part of an hin unto a ram, and a fourth part of an hin unto a lamb: this is the burnt offering of every month throughout the months of the year.
Num_28:31 Ye shall offer them beside the continual burnt offering, and his meat offering, (they shall be unto you without blemish) and their drink offerings.
Num_29:6 Beside the burnt offering of the month, and his meat offering, and the daily burnt offering, and his meat offering, and their drink offerings, according unto their manner, for a sweet savour, a sacrifice made by fire unto the LORD.
Num_29:11 One kid of the goats for a sin offering; beside the sin offering of atonement, and the continual burnt offering, and the meat offering of it, and their drink offerings.
Num_29:19 And one kid of the goats for a sin offering; beside the continual burnt offering, and the meat offering thereof, and their drink offerings.
Num_29:39 These things ye shall do unto the LORD in your set feasts, beside your vows, and your freewill offerings, for your burnt offerings, and for your meat offerings, and for your drink offerings, and for your peace offerings.
Deu_12:6 And thither ye shall bring your burnt offerings, and your sacrifices, and your tithes, and heave offerings of your hand, and your vows, and your freewill offerings, and the firstlings of your herds and of your flocks:
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