Joseph and Aseneth book is a “romance,” telling the story of Joseph’s marriage to Aseneth, the daughter of Potiphera (called Pentepheres in this book.) Like the book of Jubilees, the book attempts to answer a question which many people have about the story of Joseph. If Joseph was such a godly Jew, how could he marry an Egyptian, especially one whose father is a pagan priest? The book was written in Greek and seems to have been a Jewish book, although there are Christian interpolations (possibly the honeycomb sequence, for example, which mentions the “bread of life.”) The book may have been known in the fourth century A.D. since it is mentioned in the Pilgrimage of Etheria. This book is a list of “holy sites” written about A.D. 382. The reference to Asenath’s house is found in a fragment of the work in Peter the Deacon of Monte Cassino’s On the Holy Places, which is dated to about A.D. 1137.
It is probable that the book uses the LXX, making for a date of no earlier than 100 B.C. If the work is from Alexandria (again, the scholarly consensus), then it is unlikely to have been written much after the Jewish revolt under Trajan, A.D. 115-117. A major argument in favor of Egypt is that Asenath is the heroine, the only convert to Judaism from Egypt. If it was from Palestine, then Ruth or Rahab might have been better examples of pagan conversions, see OTP 2:187-188. This argument weakens if the book is an apologetic explaining why Joseph married an Egyptian, or an explanation of how Joseph married a gentile without punishment, aimed at Diaspora Jews tempted to marry gentiles. Like Reuben or Judah in Jubilees, the story may be intended to explain that just because Joseph “got away with it” does not mean you can!
The book falls into two parts. The first is the “romance” between Joseph and Asenath (chapters 1-21). This romance is more about repentance and gentile conversion than romantic love. From the perspective of the book, it is entirely possible for a gentile to truly convert to Judaism. Asenath is so thorough a convert she receives a heavenly visit which confirms her resolve. In order to convert she must completely reject her former idolatrous ways, a point made several times in the book, including the eating of food associated with these idols. This may play into the background of the issue of eating meat sacrificed to idols which turns up at several points in the New Testament, especially in Pauline letters.
As Christianity spread into Gentile regions, the meal became a potential problem on two levels. Some Jews appear to have been more than uncomfortable eating with Gentiles, especially those that were not of the “God-Fearers.” A second and related reason was the potential for non-kosher foods to be eaten, included meats that had been sacrificed to idols. To the Gentile, this was not a problem, since they never cared about it before Christ, and it isn’t really a problem after becoming a Christian for them. But to the Jew, this is a sin! Such food is unclean so they could not eat it in good conscious. The issue of table fellowship appears in Galatians 2:11-18. Peter had shared the table with Gentiles, but after a visit from “certain people from James” he withdrew from eating with Gentiles. Asenath indicates that, at least for some Jews, the food laws were of critical importance for true conversion. Circumcision may be the primary “boundary marker” but it is obviously not an issue for Asenath.
The second part of the book concerns a plot by the son of the Pharaoh to kill his father to revenge his losing Asenath to Joseph. This plot goes wrong when Asenath is caught in the trap. The son of the Pharaoh is injured in the attack and dies soon after. This section has less to do with New Testament issues than the first, although there is a continuation of the theme that Asenath is more righteous than the (Jewish) sons of Bilah and Zilpah.