Well, so let's employ some Bible hermeneutics and allow Scripture to explain itself:
According to the Bible, adoption in Biblical times was an accepted practice among the Hebrews. Please read the following from The New Unger's Bible Dictionary:
Greek: huiothesia, the "placing" as a "son". The admission of a person to some or all of the privileges of natural kinship. As the practice of adoption was confined almost exclusively to sons - the case of Esther being an exception - it probably had its origin in the natural desire for male offspring. This would be especially true where force, rather than well-observed laws, decided the possession of estates.
Hebrew: Abraham speaks of Eliezer (Gen 15:3), a house-born slave, as his heir, having probably adopted him as his son. Jacob adopted his grandsons Ephraim and Manasseh, and counted them as his sons (48:6), thus enabling him to bestow through them a double portion upon his favorite son, Joseph. Sometimes a man without a son would marry his daughter to a freed slave, the children then being accounted her father's; or the husband himself would be adopted as a son (1 Chron 2:34).
Most of the early instances of adoption mentioned in the Bible were the acts of women who, because of barrenness, gave their female slaves to their husbands with the intention of adopting any children they might have. Thus Sarah gave Hagar to Abraham, and the son (Ishmael) was considered the child of Abraham and Sarah (Gen 16:1-15). The childless Rachel gave her maid, Bilhah, to her husband (30:1-7) and was imitated by Leah (30:9-13). In such cases the sons were regarded as fully equal in the right of heritage with those by the legitimate wife. (From The New Unger's Bible Dictionary. Originally published by Moody Press of Chicago, Illinois. Copyright (c) 1988.)
Here's more from another source:
ADOPTION: The taking of one as a son who is not so by birth. (I) Natural: As Pharaoh's daughter adopted Moses; Mordecai Esther; Abraham Eliezer (as a slave is often in the East adopted as son) (Gen 15:2-3); Sarai the son to be born by Hagar, whom she gave to her husband; Leah and Rachel the children to be born of Zilpah and Bilhah, their handmaids respectively, whom they gave to Jacob their husband.Soooo ... let's discuss Mary and HER rights!
The handmaid at the birth brought forth the child on the knees of the adoptive mother (Gen 30:3); an act representative of the complete appropriation of the sons as equal in rights to those by the legitimate wife. Jacob adopted as his own Joseph's two sons, Ephraim and Manasseh, on the same footing as Reuben and Simeon, his two elder sons (Gen 48:5). Thereby he was able to give Joseph his favorite son more than his single share, with his brothers, of the paternal heritage.
The tribes thus were 13, only that Levi had no land division; or Ephraim and Manasseh were regarded as two halves making up but one whole tribe. In 1 Chron 2 Machir gives his daughter to Hezron of Judah; she bore Segub, father of Jair. Jair inherited 23 cities of Gilead in right of his grandmother. Though of Judah by his grandfather, he is (Num 32:41) counted as of Manasseh on account of his inheritance through his grandmother.
So Mary, being daughter of Heli, and Joseph her husband being adopted by him on marrying his daughter, an heiress (as appears from her going to Bethlehem to be registered in her pregnancy), Joseph is called in Luke's genealogy son of Heli. (From Fausset's Bible Dictionary, Electronic Database Copyright (c)1998 by Biblesoft)
Mary should be disqualified to transfer the rights of her lineage to her son Yeshua - except for a little known exception to the rule....
In Matthew 1:1-16 and Luke 3:23-38 we are presented with two genealogies of Yeshua. On the surface these different listings would appear to be a contradiction in the scriptures. The genealogy found in Matthew's gospel is the lineage of Yeshua's earthly father Joseph, while the genealogy found in Luke's gospel is the lineage of Yeshua's mother Mary. Conventional "wisdom" suggests that Matthew's lineage is Joseph's and Luke's is Mary's - but this is BACKWARDS. Matthew's Gospel -- as the Aramaic exclusive reading of Matthew 1:16 and 1:19 PROVES--is MARY's Gospel, and she is descended from Solomon.
Once you have established that the line is indeed Mary's you must deal with a second difficulty: The rights of the line are not passed through the mother, only the father. Even though Mary, through her lineage, was of the Davidic bloodline, she should be excluded from being able to pass those rights of the bloodline because of being a female (Deut 21:16).
So it is not enough to prove that Mary was an unblemished descendant of David; she also had to be a male to transfer the rights. Therefore she would be disqualified to transfer the rights to her son Yeshua, except for a little known exception to the rule!
In Numbers 26 we are introduced to Zelophehad. Zelophehad, we are told, had no sons, only daughters. In Numbers 27, following the death of Zelophehad, the daughters of Zelophehad came before Moses and argued their plight. Because their father had died with no sons, all of their rights of inheritance were to be lost and they felt this was unfair. So Moses prayed to God and God gave Moses an exception to the rule.
YHWH told Moses that the inheritance CAN flow through a female, IF they fulfill two requirements: (1) There must be no male offspring in the family (Numbers 27:8) and (2) if the female offspring should marry, they must marry within their own tribe (Numbers 36:6).
Now we come back to Mary. On the surface she should be unable to transfer the rights to her Son. But when you research you find that Mary had NO brothers, AND Mary did indeed marry within her own tribe to Joseph. What an awesome God we serve Who set in order the requirements to allow the virgin birth to take place 1,400 years in advance!
A footnote to Matthew 1 from the Aramaic English New Testament (AENT) says this:
The word gowra designates a protector-male or guardian; the context of this verse determines its specific meaning. Y'shua elsewhere says "which one of gowra, if he has a son...."; obviously "father" is intended. "Gowra" also applies to other forms of protector-male type relationships depending on the context, such as "husband", "son", and so forth. Ancient Aramaic Matthew ends at verse 17, not verse 25.
The text not only establishes the subject, but shifts from "background history" into the present, from intro to body. This means that the Yosip in verse 16 (the guardian or adopted father of Miriyam (Mary)) is not the same Yosip as the husband of Miriyam in verse 19.
There is no reason for Matthew to use two different words for the same individual, whereas gowra sometimes means "husband" but can also mean "father". The other term baalah can only mean "husband". On the other hand, there would most definitely be a reason to differentiate two men named Yosip, one being the adopted father, the other the husband of Miriyam. With this differentiation we now have three full sets of 14 generations, which satisfies the demands of verse 17.
Furthermore ... When you read thoroughly the details of Zelophedad's daughters it is clear that is exactly what it is about: Females inherit the assets of their father when there is no male heir. This is stated DIRECTLY:
Numbers 27: 7 'Zelophehad's daughters are right in what they say. You will indeed give them a property to be their heritage among their father's kinsmen; see that their father's heritage is passed on to them. 8 Then speak to the Israelites and say, "If a man dies without sons, his heritage will pass to his daughter.
9 If he has no daughter, the heritage will go to his brothers. 10 If he has no brothers, his heritage will go to his father's brothers. 11 If his father has no brothers, his heritage will go to the member of his clan who is most nearly related; it will become his property. This will be a legal rule for the Israelites, as Yahweh has ordered Moses."' (NJB)
Proof of this is also indirectly stated with Joseph and Mary returning to Bethlehem. Mary is attached to that inheritance through her husband but she also inherits from her family without there being a male heir.
And let's not forget, Talmud says a child is considered Jewish if his MOTHER is Jewish....And Torah says land can only pass WITHIN THE TRIBE it is allotted to. YHWH calls it an INHERITANCE. And with the Levites YHWH says, "I am their inheritance"...so obviously being from a tribe is an asset if you inherit YHWH....