Heli is a Biblical individual mentioned in Luke 3:23 whom many Protestant scholars consider is the father of Mary, mother of Jesus.

The Lukan genealogy mentions Joseph, not Mary, but does not have the word "son of" in the Greek text, leading to the suggestion that "son-in-law" of Heli is intended:

Luke 3:23 Jesus, when he began his ministry, was about thirty years of age, being the son (as was supposed) of Joseph, [the son] of Heli, 24 [the son] of Matthat, [the] son of Levi

Two genealogies of Jesus

Since Joseph cannot be both "begotten of Jacob", descended from Solomon

Solomon

Solomon , according to the Book of Kings and the Book of Chronicles, a King of Israel and according to the Talmud one of the 48 prophets, is identified as the son of David, also called Jedidiah in 2 Samuel 12:25, and is described as the third king of the United Monarchy, and the final king before...

 (according to Matthew 1), and also "of Heli", descended from another of David's sons, Nathan

Nathan (son of David)

Nathan was the third of four sons born to King David and Bathsheba in Jerusalem. He was an older brother of Solomon.In the New Testament, the genealogy of Jesus according to the Gospel of Luke traces Jesus' lineage back to King David through the line of Nathan, although the Gospel of Matthew...

 (according to Luke 3) various explanations have been proposed for the Luke genealogy actually to be that of Mary. The view is relatively late; advocates of this view include John of Damascus

John of Damascus

Saint John of Damascus was a Syrian monk and priest...

 (8th C), Annius

Annius

Annius is the nomen of the Roman gens Annia. It may refer to male members of that family.Annius may also refer to Annio da Viterbo, a fifteenth century Dominican friar, scholar, and historian, remembered chiefly for his fabrications....

 (15th C), Luther

Martin Luther

Martin Luther was a German priest, professor of theology and iconic figure of the Protestant Reformation. He strongly disputed the claim that freedom from God's punishment for sin could be purchased with money. He confronted indulgence salesman Johann Tetzel with his Ninety-Five Theses in 1517...

, Bengel

Bengel

Bengel is an Ortsgemeinde – a municipality belonging to a Verbandsgemeinde, a kind of collective municipality – in the Bernkastel-Wittlich district in Rhineland-Palatinate, Germany.-Location:...

 and Lightfoot

Lightfoot

Lightfoot may refer to the following people:* Chris Lightfoot , a former English footballer* Claude Lightfoot, an African-American activist* David Lightfoot, an Australian film producer* Edwin N...

. Harry A. Ironside

Harry A. Ironside

Henry Allen "Harry" Ironside was a Canadian-American Bible teacher, preacher, theologian, pastor, and author.-Biography:...

 (1930) considered that it was simply preference to drop women's names out of the genealogy, hence Joseph was son in law of Heli.

Prior to the explanation above, the explanation of Sextus Julius Africanus

Sextus Julius Africanus

Sextus Julius Africanus was a Christian traveller and historian of the late 2nd and early 3rd century AD. He is important chiefly because of his influence on Eusebius, on all the later writers of Church history among the Fathers, and on the whole Greek school of chroniclers.His name indicates that...

 that there had been a levirate marriage

Levirate marriage

Levirate marriage is a type of marriage in which the brother of a deceased man is obligated to marry his brother's widow, and the widow is obligated to marry her deceased husband's brother....

 and that Joseph's grandfather Mattan (descendant of Solomon) had had a wife called "Esther" (not recorded in the Bible) with whom he fathered Jacob (Joseph's father), but Matthan died and Esther married Heli's father Melchi (descendant of Nathan). Then when Heli died childless (again not recorded in the Bible) Joseph's father Jacob took Heli's wife to raise up children for Heli and left Joseph adopted in Heli's widow's house. -----------------correction----------------correction---------------correction

The curse on the Solomonic line

If the situation is reversed, Matthew's genealogy is that of Mary, Luke's of Joseph, then there is a problem with the curse on the Solomonic line, dating from the time of Jechoniah where Jeremiah

Jeremiah

Jeremiah Hebrew：יִרְמְיָה , Modern Hebrew:Yirməyāhū, IPA: jirməˈjaːhu, Tiberian:Yirmĭyahu, Greek:Ἰερεμίας), meaning "Yahweh exalts", or called the "Weeping prophet" was one of the main prophets of the Hebrew Bible...

 pronounced that no descendant of Jeconiah would again sit on the throne of Israel. Although Israel had at least one Solomonic descendant, Zerubbabel

Zerubbabel

Zerubbabel was a governor of the Persian Province of Judah and the grandson of Jehoiachin, penultimate king of Judah. Zerubbabel led the first group of Jews, numbering 42,360, who returned from the Babylonian Captivity in the first year of Cyrus, King of Persia . The date is generally thought to...

 as governor under the Persians, Zerubbabel never was crowned king.

Saint Joachim and Saint Anne

The apocryphal Protoevangelium of James gives the story of Saint Joachim and Saint Anne

Saint Anne

Saint Hanna of David's house and line, was the mother of the Virgin Mary and grandmother of Jesus Christ according to Christian and Islamic tradition. English Anne is derived from Greek rendering of her Hebrew name Hannah...

as the parents of Mary. This is largely followed in Catholic, Orthodox, and Anglican tradition.