If maybe you thought I was some kind of provocatively heretical guy…… then absolutely, absolutely not!!!!! And if you really have no opinion on the subject, then my words are null and void…..

What does that have to do with heresy? And besides, what’s so bad about heretics? I really don’t have an opinion. How can one know?

Okay…… so without a doubt this is the first time I’m left with a question mark even after looking for answers from you (after hearing all the “standard” and unconvincing explanations)

As is known, there is a dispute about this in our sources. Nachmanides, for example, holds that this was a good custom instituted by the sages of that period.

True, we can’t know with certainty, but based on what is known to us today, Nachmanides’ view seems plausible.
I’ll explain: the custom of levirate marriage (by the whole family, according to a biological order of precedence) also existed among the Hittites and Assyrians. Research into the laws of the ancient Near East shows that the Assyrian and Hittite legal conception stems from a general principle that the woman is part of the family property for which a bride-price was paid, and therefore she *must* marry someone from the family (there is evidence for this from inheritance law and more).
In this case, the Torah adopted the local law and made it more moral (the Torah law protects the woman and her ability to sustain herself if she wants that, rather than protecting the husband as in their systems).

Therefore, it is not unreasonable that in this case we are dealing with a good custom that was accepted among the ancient Israelites (in addition to the binding halakhic law), which was adapted to the more moral Torah law (after all, here Naomi did not force Ruth to enter levirate marriage, but released her to go her own way).

For more on the academic side of the issue: Laws of the Ancient Near East, Dr. Philip Kornngreen? (a judge and secular Zionist activist in the first half of the 20th century), Yavneh Publishing, 1944. It is an important book and very hard to obtain; it is probably in academic libraries and the like. The copy I have is falling apart; I took it out of its plastic sleeves because it was clear to me that it discusses this.

What do you mean by other relatives? What is the order of precedence? When you write “biblical period,” do you mean the Five Books of Moses, or also the time of the Book of Ruth (the period of the Judges)?
Redemption in the Hebrew Bible includes levirate marriage and is not separate from it. That is what Boaz said to the first potential levir: if you wish to marry her in levirate fashion, redeem the field and Ruth will automatically be yours. In practice he said: if you redeem the field, Ruth is yours. And he refused because he already had a wife and an inheritance. So he waived it, and then Boaz bought the field and acquired Ruth.

The word “levirate marriage” is not mentioned in the Book of Ruth, and as I wrote, the accepted interpretation is that this is not levirate marriage but a custom called redemption, since according to Jewish law levirate marriage applies only to brothers, as the plain meaning of the verse says: “If brothers dwell together…….” But from the Maharsha in Yevamot (in the passage about a mamzeret who fell to levirate marriage) it emerges that in Ruth’s period levirate marriage was practiced also among other relatives, and that is essentially the Karaite claim, who interpreted “If brothers dwell…..” as meaning not necessarily literal brothers but family relatives in general…..

It seems to me you’ve made some simple things complicated.
And you’re right, it doesn’t say “levirate marriage” here in Ruth.

So your question is actually very good, if I understood after reading it again: what is the difference between levirate marriage and redemption? And is there a change between the redeemers in the time of the Five Books of Moses and the period of Ruth?

Let us bring the verse: Deuteronomy:
“If brothers dwell together, and one of them dies and has no son, the wife of the dead man shall not be married outside the family to a stranger; her husband’s brother shall go in to her, take her to himself as a wife, and perform levirate marriage with her. And it shall be that the firstborn whom she bears shall succeed in the name of his dead brother, so that his name not be blotted out from Israel. But if the man does not wish to take his brother’s widow, then his brother’s widow shall go up to the gate to the elders and say: ‘My husband’s brother refuses to establish for his brother a name in Israel; he will not perform the duty of a husband’s brother to me.’ Then the elders of his city shall call him and speak to him; and if he stands and says: ‘I do not wish to take her,’ then his brother’s widow shall come near to him in the presence of the elders, remove his shoe from upon his foot, spit before him, and answer and say: ‘So shall be done to the man who will not build up his brother’s house.’ And his name shall be called in Israel: ‘The house of him whose shoe was removed.’”
Genesis 38:
“And Er, Judah’s firstborn, was evil in the eyes of the Lord; and the Lord put him to death. Then Judah said to Onan: ‘Go in to your brother’s wife and perform levirate marriage with her, and raise up offspring for your brother.’ But Onan knew that the offspring would not be his; so whenever he came to his brother’s wife, he wasted it on the ground, so as not to give offspring to his brother. And what he did was evil in the eyes of the Lord, and He put him also to death. Then Judah said to Tamar his daughter-in-law: ‘Remain a widow in your father’s house until my son Shelah grows up’—for he said, ‘Lest he also die like his brothers.’ So Tamar went and lived in her father’s house.”
Ruth:
“Now Boaz had gone up to the gate and sat there; and behold, the redeemer of whom Boaz had spoken passed by. So he said, ‘Turn aside, sit here, so-and-so.’ And he turned aside and sat down. And he took ten men of the elders of the city and said, ‘Sit here’; and they sat down. Then he said to the redeemer, ‘Naomi, who has returned from the field of Moab, is selling the parcel of land that belonged to our brother Elimelech. And I thought I should disclose it to you and say: Buy it in the presence of those sitting here and in the presence of the elders of my people. If you will redeem it, redeem it; but if you will not redeem it, tell me, that I may know, for there is none besides you to redeem it, and I come after you.’ And he said, ‘I will redeem it.’ Then Boaz said, ‘On the day you buy the field from the hand of Naomi, you also acquire Ruth the Moabite, the wife of the dead man, to raise up the name of the dead upon his inheritance.’ Then the redeemer said, ‘I cannot redeem it for myself, lest I impair my own inheritance. Redeem for yourself my right of redemption, for I cannot redeem it.’ Now this was formerly the custom in Israel concerning redemption and exchange, to confirm any matter: a man would draw off his shoe and give it to his neighbor; and this was the manner of attestation in Israel. So the redeemer said to Boaz, ‘Buy it for yourself,’ and he drew off his shoe. Then Boaz said to the elders and to all the people, ‘You are witnesses this day that I have bought from the hand of Naomi all that belonged to Elimelech and all that belonged to Chilion and Mahlon. Also Ruth the Moabite, the wife of Mahlon, I have acquired to be my wife, to raise up the name of the dead upon his inheritance, so that the name of the dead not be cut off from among his brothers and from the gate of his place. You are witnesses this day.’”

Common denominator: here she went up to the gate, and there he went up to the gate.
He went to the elders, and here too he went to the elders.
“Thereby not to give offspring to his brother,” and here, “to raise up the name of the dead upon his inheritance.”
My answers, in my opinion only:
1. Before the Torah there was no inheritance law, and so it says “levirate marriage”—see Genesis 38:8—and then the whole purpose of levirate marriage is to raise up offspring for his brother.
After the Torah there was inheritance, and it says that if a brother dies then yes, someone has to marry her. Is it specifically an actual brother? Yes and no; from Ruth we saw that it was not. If the laws changed? Not necessarily, because look: it says in Deuteronomy that “the wife of the dead man shall not be outside to a strange man,” meaning that in Ruth we saw that she was indeed taken in levirate marriage by a stranger (not an actual brother; in fact there wasn’t even an actual brother, because they were only two brothers, Mahlon and Chilion). So from the outset you ask whether there is a difference between levirate marriage and redemption? I showed the common denominator, and it says in Ruth, “Now this was formerly the custom in Israel,” meaning an already known and ancient law. “Concerning redemption and exchange,” meaning the law remained in both cases. It comes out that Boaz redeemed the field and got Ruth as part of the deal as well. This is what is called obscure in one place (in the Torah, in Deuteronomy) and explained in Ruth. Let us return and say: in Deuteronomy, “a stranger” does not mean specifically an actual brother—definitely.
Maybe the Karaites were right and maybe not, but there is no difference between redemption and levirate marriage, because levirate marriage is part of redeeming the field, since it is impossible to redeem the field without performing levirate marriage! We saw that from the Book of Ruth.
The word “levirate marriage” cannot change because of who the levir is; rather, its meaning is that the child born is named after the dead man.