@izzythepush,
The Talmud states, "Whoever brings up an orphan in his home is regarded...as though the child had been born to him." (Sanhedrin 19b).” In other words, the adopted child is to be treated as a child born to the father of that house, which means, that Heli and his descendants, who were born from the genetic line of Nathan ‘the prophet,’ who was the adopted son of King David, were legitimate heirs to King David, although originally, not to the throne of Israel, as the prophesied Messiah had to come through the genetic line of Solomon.
Heli and his descendants only became heirs to the throne of David, through Nathan the adopted son of King David, when Naria, a descendant of Nathan, married Tamar, a female descendant of King Solomon, who bore to Naria a son by the name “Salathiel.” After the death of Naria, Tamar was taken to wife by King Jehoiachin, whose only biological son with Tamar, was Zedekiah who died prematurely in Childhood.
According to Torah law, Nathan the adopted son of King David, and Nathan’s descendants, were legitimate heirs of King David, but not in the ancestral line of the promised Messiah, who was to be born of the seed of Solomon, until Naria the descendant of Nathan coupled with Tamar the descendant of Solomon, to produce Salathiel the ancestor of Jesus, who has been made High Priest (From the tribe of Levi=Nathan) and King (From the tribe of Judah=Solomon) in the order of Melchizedek.
David Hughes the noted Genealogist of the Ancient World Lineages, states that King Jeconiah’s only son, with Queen Tamar, ‘Prince Zedekiah,’ died prematurely in childhood, and in 586 BCE King Zedekiah, the last king of Israel, whose original name Mattaniah, was the son of Josiah and the uncle of Jehoiachin. King Zedekiah/Mattaniah, was taken prisoner and his sons were executed in front of him, after which, his eyes were gouged out, and there in Babylon, he remained blinded in exile for the rest of his life and it appeared that the entire royal lineage of King David through God’s chosen son, Solomon, had been exterminated.
With all the known direct lineages of male heirs to the lineage of King Solomon the son of King David and Bathsheba now extinct, Queen Tamar II became the dynastic heiress preserving not only the Lineage of King Solomon, but also became the inter-dynastic link, or the vital crossover heiress merging the non-royal Nathan lineage with the royal lineages of King Solomon. With the addition of Tamar representing the mainline descendants of King David, we now can understand the linkage between the two prime royal and non-royal lineages to the ancestry of the Jewish Messiah Yehoshua ben Yosef (Jesus son of Joseph the son of Alexander Helios a descendant of Nathan).
Jesus carried in his genes the potent fusion of Davidian and Zadokian bloodlines. He carried the potent bloodline of the royal mantle as a Priest-King of Israel and the messianic mantle as the Maschiach Yisra’el (Messiah of Israel) of the House of David.