Introduction: The Bible not only provides man with answers to such great questions as man’s origin, purpose, and destiny, but it is the source of faith (Gen. 1, 2; Eccl. 12: 13, 14; Matt. 25: 46). Paul wrote, "so then faith cometh by hearing and hearing by the word of God" (Rom. 10: 17). The saving faith of the scriptures is active and productive (Jas. 2: 19-26, Gal. 5: 6). However, sometimes man encounters matters in the Bible which tend to weaken his faith and cause doubt.

I. Cain was the first son of Adam and Eve (Gen. 4: 1).

  A. After Cain murdered his brother, God sent Cain away (Gen. 4: 8-14).

  B. The Bible tells us "Cain knew his wife, and she conceived…" (Gen. 4: 17).

  C. The question is how did Cain find a wife if only he, Adam, and Eve were living at this time.

II. The matter of Cain finding a wife has given way to many fanciful notions

  A. Some have argued there was a pre-adamic race or people from a parallel world and out of these Cain found a wife. This kind of thinking supplied much material to the old television program, The Twilight Zone.

   a. Some in a feeble effort to satisfy the doubters and "protect" the Bible have suggested this parallel world as a possibility. However, the Bible says Adam was the "first man" (I Cor. 15: 45). The Bible also says Eve was the mother of all living (Gen. 3: 20). Hence, the parallel world theory is not plausible or tenable.

  B. Another view is that Cain simply married his sister.

   a.As a rule, the Bible does not specifically mention the birth of daughters. However, we are told regarding Adam, "…and he begat sons and daughters" (Gen. 5: 4).

   b. It is important to realize that the Bible does not really say when Cain found his wife (cp. Gen. 4: 16, 17).

   c. The Bible does not say, either, that Cain married his sister, but such a conclusion appears necessary.

III. The Bible teaches against marriages of close relatives

  A. This argument is offered (usually by those attempting to disprove the Bible) in an effort to prove Cain’s wife was not his sister.

   a. Some argue that if you offer as a plausible explanation that Cain married his sister, you are forcing the Bible to contradict itself (the scriptures forbid such marriages , Lev. 18). Of course, Cain had not been very concerned about doing God’s will – he committed murder!

  B. It is true that later such marriages were forbidden (Lev. 18).

   a. One probable reason for such prohibition seems to have been the genetic dangers of brother-sister marriages. Such marriages during the time of Leviticus 18 and today can and often do involve mutant genes in the genetic systems of such couples. However, in the case of Adam and Eve, the progenitors of the human race, and their children there would have been no such condition or danger, according to geneticists.