Was Rahab the Harlot in the Line of Jesus?
If Rahab the harlot married (or continued to have marital relations) after her conversion while her former sex partners were alive, then we can come to one of the following conclusions:
(1) Since sex equals marriage, Rahab was living in adultery after her conversion; thus, believers can live in adultery;
(2) Rahab was not living in adultery after her conversion; thus, sex does not equal marriage.
Obviously, believers cannot be adulterers or adulteresses (1 Corinthians 6:9-10), so this eliminates #1. Thus, if Rahab the harlot married (or continued to have marital relations) after her conversion while her former sex partners were alive, then this alone is enough proof that marriage does not equal sex and that marrying after having sex with at least one other person (while the previous partner(s) is/are still alive) is not adultery. It would seal the deal.
But is it not obvious that she married or continued to have marital relations after her conversion, since she is mentioned in the line of Jesus (Matthew 1:5)?
Here are excerpts of an article I found online (this is not an endorsement of the author or of anything else the author may have written):
"Who, then, was this female ancestor of our Lord -- Rachab -- who is stated, in Matthew 1:5, to have married Salmon the son of Naashon, a prince of the Royal line of Judah, some time either before or after the Israelites occupied the Promised Land?
Every Bible translator and commentator, without exception, associates her with, or directly identifies her as `Rahab the harlot' who was saved alive from the massacre of Jericho. ...
Several attempts have been made:
a. to identify Rahab as an Israelite descendant of Sherah, the daughter of Ephraim, who went to Canaan about two centuries or so before the Exodus -- 1 Chronicles 7:24 -- and built the strongholds of Beth-horon and Uzzen-sherah some 25 miles west of Jericho
b. to clear her name of the term "harlot" by describing her as a `widow' or an `innkeeper' or as a `trader in flax'.
But the term `harlot' is not only used by Joshua in the Old Testament; it is used again both by Paul and James in the New Testament 1500 years later. Thus there had been ample opportunity since Joshua's day to clear her name from that obnoxious designation if there had been no justification for it. ... Moreover Joshua, himself, was a ninth generation descendant of Ephraim (1 Chronicles 7:24-27) and would have been related to Rahab if she was, in truth, a descendant of Ephraim's daughter Sherah.
Therefore not only would Joshua have given his two spies careful instructions for rescuing Rahab on the grounds of consanguinity but he would also have cleared her name of any undeserved accusations of being a harlot had they not been true. ...
Joshua 6:25 states that Rahab was given land in the midst of Israel in return for risking her own life by hiding the two spies that were sent to Jericho. Josephus in his "Antiquities of the Jews", Book 5 chapter 1, sections 2 and 7, records the same story but neither he nor Joshua make any reference to a marriage taking place between Rahab and Salmon. That deafening silence is itself the strongest proof that no such marriage did take place. ...
However, let us assume for a moment that Salmon did marry Rahab the harlot within a year or so of the fall of Jericho, and that Boaz was born a year or so after that. If such were the case, then Boaz would have been about 115 years old when he married Ruth! On the other hand, if we assume that Rahab was about 30 years of age when Jericho fell, and that Salmon did not marry her till 30 years or more later, then not only would Rahab have been at least 60 years of age and no longer able to bear children, but Boaz, even if born 30 years after the fall of Jericho, would still have been 85 years of age when he married Ruth. ...
... Thus all the evidence confirms the fact that Salmon did not marry Rahab the Canaanite harlot. In fact, the Bible states, in plain writing, that Salmon married a different woman altogether. A woman with a different name, and without any distinguishing appellation, obnoxious or otherwise, attached to her name. It is the religious translators and commentators who have made the mistake in translation and identified Salmon's wife as the harlot of Jericho. …
This is not just another way of spelling or of pronouncing 'Rahab' or 'Rakhab' either in Greek or in Hebrew. 'Rachab' is a different name altogether in the 'original' Greek. Therefore it cannot refer to Ra'ab the harlot, it can only refer to a different woman. Now it has been shown time and time again that God never uses two different words, or two different names in the same verse or context to refer to the same thing or person. The different words or names are always put there to draw our attention to the fact that He is referring to different things or persons.
But Matthew 1:5, Hebrews 11:31 and James 2:25 cannot be classified as being 'in the same context'. Therefore more positive methods have been used in these passages to identify the person concerned precisely and exactly, and to distinguish between one person and another. Thus in Hebrews 11:31 and James 2:25, the reader is told explicitly that these passages refer to Ra'ab the harlot of Jericho:
a. by stating her name,
b. by repeating her designation of a harlot,
c. by mentioning the action which she took to help the two spies. These are all positive marks of identification.
On the other hand in Matthew 1:5 Rachab the wife of Salmon is clearly distinguished from ANY identification or association in any way with the harlot of Jericho:
1. by the different spelling of her name in the 'original' Greek,
2. by the different pronunciation of her name,
3. by the absence of any offensive designation attached to her name,
4. by the absence of any reference to Jericho or any activity that took place there.
Nor is the absence of any such additional information about Rachab designed to 'cover up' possible unfavourable personal references to individual members of Israel's Royal Line and of the human ancestors of Jesus in this genealogy. The Bible does not shrink from stating unsavoury 'incidents' in the lives of any of Israel's famous people. This is demonstrated in the very next verse (Matthew 1:6) by the cutting reference to Bathsheba -- not by recording her name, but by bringing her name to mind only through her degrading act of adultery with King David. Again, there is the story of Judah's seduction by Tamar as told in Genesis 38:11-30.
This shows that the "Rahab" of Matthew 1:5 is not the same person as the "Rahab" of Joshua 2 and 6, Hebrews 11:31, and James 2:25. Rahab the harlot was not the person who married Salmon and was not the great-great-grandmother of David and was not in the line of Jesus Christ.
See the article "What Constitutes Marriage."