I was wondering if there is a mistranslation in the bible regarding the lineage of Mary/Joseph.
God states that Jesus will be a direct descendant of David, but since Jesus’ Father is God, Jesus has to be a direct descendant of David through Mary’s lineage (otherwise there is no blood relation to David). In Matthew 1:2-16 it provides a ‘family tree’ that claims to end with “Jacob the father of Joseph, the husband of Mary. Of her was born Jesus who is called the Messiah.” This indicates Jesus is connected to David only through the marriage of Mary to Joseph, who is then a descendant of David. This doesn’t make Jesus a DIRECT descendant…
Furthermore, Matthew 1:17 states “Thus the total number of generations from Abraham to David is fourteen generations; from David to the Babylonian exile, fourteen generations; from the Babylonian exile to the Messiah, fourteen generations.” By my count there are only 13 in the 3rd group.
Your question has a simple answer, but one that’s not apparent from Scripture. In Biblical times there was no word for father-in-law, just as there was no word for grandfather. Joseph can’t be the son of both Jacob and Heli. According to the Jerusalem Talmud (Chag. 77,4), Heli was actually Mary’s father making him Joseph’s father-in-law. The reason the two genealogies are different is that Joseph was descended from Solomon while Mary was a descendant of Solomon’s older brother Nathan.
So Joseph and Mary were actually cousins although many times removed. Since Heli had no sons, Mary had to find a husband from the tribe of Judah like herself to protect her father’s estate.(See Numbers 36) She also needed a direct descendant of Solomon to perfect her son’s claim to the throne of David, since Nathan’s descendants weren’t of the Royal line.
Joseph fit the bill on both accounts but like every other descendant of Solomon’s carried a blood curse disqualifying any biological son of his from ever being King of Israel.(Jeremiah 22:28-30) Since Joseph was not the Lord’s biological father, he could adopt Him, qualifying Him to be King without passing Him the curse.
Thus, because of the virgin birth, Jesus became the only one in Israel qualified to sit on David’s throne, and remains so to this day.
As far as the genealogies go, notice that the passage reads “fourteen from David to the exile to Babylon and fourteen from the exile to the Christ.” (Matt 1:17) Technically the exile occurred before the reign of Jeconiah ended, so Matthew counted him again at the start of the third list, giving each 14 names.