Joseph was the father of Jesus.
30 Therefore being a prophet [David], and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne;
Acts 2:30 KJV
23 Of this man's seed [David’s] hath God according to his promise raised unto Israel a Saviour, Jesus.
Acts 13:23 KJV
More references(KJV): Romans 1:3 (made of the seed of David); 2 Timothy 2:8 (Jesus Christ of the seed of David); Hebrews 2:16 (the seed of Abraham); Revelation 22:16 (the offspring of David)
Joseph was not the father of Jesus.
18 Now the birth of Jesus Christ was on this wise: When as his mother Mary was espoused to Joseph, before they came together, she was found with child of the Holy Ghost.
Matthew 1:18 KJV
34 Then said Mary unto the angel, How shall this be, seeing I know not a man?
35 And the angel answered and said unto her, The Holy Ghost shall come upon thee, and the power of the Highest shall overshadow thee: therefore also that holy thing which shall be born of thee shall be called the Son of God.
Luke 1:34-35 KJV
Merry Christmas
Christmas is maybe the most well-known Christian feast; the birth of Jesus Christ. Joseph and Mary pass the night in a stable and then Mary begot her firstborn child. All the ins and outs of this event are common knowledge, e.g. that Jesus was born of the Hoy Spirit and Joseph was not his real father. However, the SAB critic seems to know better …
Biblical inconsistency?
He sees a contradiction in the biblical information that Jesus was born of the Holy Spirit and that Jesus was of the seed of David (or even Abraham). It seems that the critic’s argument is: OK, the seed (Greek: sperma) of David refers to a male descendant of David that will give birth to the Messiah. That would be Joseph. So the Bible seems to be inconsistent concerning one of the most important Christian issues. Did Mary conceive through the Holy Spirit or was Joseph the biological father?
Meaning of 2000 years later …
Apparently the critic has read for ‘seed’: sperm, male cells for reproduction. Unfortunately he has implemented a meaning of 2000 years later in the Biblical text and that isn’t a proper way of acting.
In the Biblical vernacular the word seed (Classical Greek: sperma) has the basic meaning of tiny grains of plants, already fertilized and ready to bring forth new plants. E.g. mustard seed, the smallest seed of the garden plants in Galilee; grains of corn harvested for food or sowing-seed.
In the same way the descendants of a person are his seed (Classical Greek: sperma), his offspring. Of course men and women belong to this offspring and not just men. So Mary was part of David’s offspring and her lineage is to be found in Luke 3:23-31. And that was the biological line from Jesus, being the son of Mary, to David.
The example of Eve and her seed
In the Greek translation of the Old Testament (LXX) of 200 BC we read in Genesis 3:15, as follows:
“And I will put enmity between thee and the woman, and between thy seed [sperma] and her seed [sperma]; it shall bruise thy head, and thou shalt bruise his heel.” An ongoing battle between snakes and men is prophesied here. Of course there is the deeper value that there will be an ongoing spiritual battle between the devil and mankind, as not only the snake but also the devil is addressed in this saying. Remarkable is the expression ‘her seed’: Eve's offspring (entire human race). Certainly not her ‘male reproduction cells’.
Critical inconsistency
It is one of the traps in the arsenal of Bible criticism to suggest wrong meanings in proper Biblical texts to put the reader on the wrong foot and to give the impression that something is very wrong with God’s Holy Word. However sound argument and a good heart will survive in this tricky field.
No Bible Contradiction