My question is how can our Lord Jesus have lineage with King David when our Lord do not have a blood relation with Saint Joseph?Answer:
To the shepherds, the angel announced the birth of Jesus as the Messiah promised to Israel: "To you is born this day in the city of David a Saviour, who is Christ the Lord." From the beginning he was "the one whom the Father consecrated and sent into the world", conceived as "holy" in Mary's virginal womb.
God called Joseph to "take Mary as your wife, for that which is conceived in her is of the Holy Spirit", so that Jesus, "who is called Christ", should be born of Joseph's spouse into the messianic lineage of David.
According to Matthew chapter 1, St Joseph is a direct descendant of King David, through Solomon and all the Kings that followed, and is in the royal lineage of the house of Judah. Since the house of Judah was the legitimate rulers of all of Israel before the United kingdom split into the southern kingdom of Judah and the northern kingdom of Israel, then the descendants of David and Solomon are the legitimate heirs to the throne.
It's true that St Joseph wasn't the biological father of Jesus, that would be Holy Spirit (Matthew 1:20 & Luke 1:35). But there is evidence that Jesus was adopted by St Joseph, and according to Jewish law and custom, would be entitled to any inheritance from His adoptive father.
When St Joseph first found out that Mary was pregnant he decided to divorce her according to the Mosaic Law, and send her away quietly. But then he had a dream in which an angel appeared and told him to take Mary as his wife, and to name the child Jesus.
When Joseph woke from sleep, he did as the angel of the Lord commanded him; he took his wife, but knew her not until she had borne a son; and he called his name Jesus.
Joseph being a righteous man, and a model for all husbands and fathers, did as he was told and took Mary as his wife. By taking her as his wife he was legally adopting her child as his own.
In verse 21 we see that Joseph also names the child, this was another indication that he was accepting the fatherhood of this child, and claiming Him as his own.
Luke 2:41 also referred to SS. Joseph and Mary as "His parents."
Virgin Birth and Adoption
According to Jewish law, your tribal affiliation and your hereditary inheritance is according to you male ancestors. But Jesus had no biological earthly father, so then He'd be a Jew without a tribe, and without royal lineage.
There were many prophesies concerning the messiah, and every one was fulfilled by Jesus. One of them being the virgin birth, but if St Joseph doesn't count as Jesus' father the there are contradictions in the prophesies. He was prophesied to be born of a virgin and also be of the trib of Judah and the line of David. If one is born of a virgin, and you get your tribal affiliation from your father, then it would be impossible to achieve both.
Except that God ordained for St Joseph to be the spous of the Blessed Mother, and by that Jesus would be a legitimate member of the tribe of Judah and the seed of David.
This is something of a foretaste for the church, in that we are not heirs to the promises of God to Abraham, Isaac and Jacob by blood, by by divine adoption.
But when the time had fully come, God sent forth his Son, born of woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons. And because you are sons, God has sent the Spirit of his Son into our hearts, crying, "Abba! Father!" So through God you are no longer a slave but a son, and if a son then an heir.
Genealogies are important
Most people breeze by the genealogies found in the Bible, partly because the names are hard to read, partly because it all seems repetitive. But every word in sacred scripture is inspired by God, and there for a reason, as St. Paul tells us;
All Scripture is inspired by God andprofitable for teaching, for reproof, for correction, and for training in righteousness
2 Timothy 3:16
Since this is an article focused on the lineage of Jesus I'd like to take a moment and point out a few more interesting things found in Matthew 1.
Here's the lineage of Christ according to St Matthew:
The book of the genealogy of Jesus Christ, the son of David, the son of Abraham. Abraham was the father of Isaac, and Isaac the father of Jacob, and Jacob the father of Judah and his brothers, and Judah the father of Per'ez and Ze'rah by Ta'mar, and Perez the father of Hezron, and Hezron the father of Ram, and Ramthe father of Ammin'adab, and Amminadab the father of Nahshon, and Nahshon the father of Salmon, and Salmon the father of Boaz by Ra'hab, and Boaz the father of O'bed by Ruth, and Obed the father of Jesse, and Jesse the father of David the king. And David was the father of Solomon by the wife of Uri'ah, and Solomon the father of Rehobo'am, and Rehoboam the father of Abi'jah, and Abijah the father of Asa, and Asathe father of Jehosh'aphat, and Jehoshaphat the father of Jo'ram, and Joram the father of Uzzi'ah, and Uzzi'ah the father of Jo'tham, and Jotham the father of A'haz, and Ahaz the father of Hezeki'ah, and Hezeki'ah the father of Manas'seh, and Manasseh the father of Amos,and Amosthe father of Josi'ah, and Josi'ah the father of Jechoni'ah and his brothers, at the time of the deportation to Babylon. And after the deportation to Babylon: Jechoni'ah was the father of She-al'ti-el,and She-alti-elthe father of Zerub'babel, and Zerub'babel the father of Abi'ud, and Abiud the father of Eli'akim, and Eliakim the father of A'zor, and A'zor the father of Za'dok, and Zadok the father of A'chim, and Achim the father of Eli'ud, and Eli'ud the father of Elea'zar, and Eleazar the father of Matthan, and Matthan the father of Jacob, and Jacob the father of Joseph the husband of Mary, of whom Jesus was born, who is called Christ. So all the generations from Abraham to David were fourteen generations, and from David to the deportation to Babylon fourteen generations, and from the deportation to Babylon to the Christ fourteen generations.
Including the names of women in a genealogy is not very common in Jewish custom, but there are four women (not including the Virgin Mary) mentioned in Matthew's genealogy.
One of the interesting things about these women is that all of them are Gentiles. This can be seen as an indication that Jesus has come for Jew and Gentile alike, and that He had come to save all the world.
The other thing about these women is that three of them are notorious for sexual sins. Tamar committed incest with her father-in-law (Genesis 38:15-26), Rahab was a prostitute from Jericho (for more on her story, read this Post), and Bathsheba had an affair with King David after he had her husband killed. This can be seen as evidence that Christ came for the sinners, not only did He dine with them and have tax collectors as disciples, He even had them in his family tree!