When discussing the meaning of words, simply checking the dictionary is usually sufficient. However dictionaries may not always give the proper meaning of a word, especially when the word has its roots in historical and religious texts and when the subject has been treated as taboo for many years.
When dealing with topics related to morality, what better source could there be than the instruction book on life given to us by the creator of life - God. However, the Bible is not a dictionary. We cannot simply look up a word in the sacred texts and expect a simple definition.
Yes, biblical scholars have produced Bible dictionaries based on their understanding of the scriptures, but the Bible itself is not one. The only real way to understand the meaning of a word in the Bible is to search out the word in its various uses and come to a conclusion which seems to be the best possible. That is what the writers of Bible dictionaries do, and that is what I have done in considering the definitions of the words "adultery" and "fornication".
Since these words occur so frequently in the Bible, it may be assumed that God definitely has something important to say about them, to which we must listen. However, it is not the intent of this study to teach "about" adultery and fornication, but rather to understand the meaning of the terms.
I will not attempt here to recreate the study I have done on the subjects, but merely to outline the method I used so you can repeat the process if you wish. In doing so, you will most likely arrive at the same conclusion at which I arrived.
On studying the word "adultery", I first listed all the references to the word I could find in my Bible using a good concordance. There were over 100 verses. I then read each one to determine if it dealt with the actual physical act of adultery, or it dealt with a spiritualization of the term - such as God calling the worship of other gods "adultery".
I studied the context of the ones dealing with the phsical act to see what they all had in common. I also compared my findings with definitions in Bible dictionaries. Then I compared my forming definition with the spiritualization of the term to see how the definition fit.
I repeated this same process with the word "fornication", also checking out synonyms used in various translations, such as "uncleanness".
Here are my conclusions, which I shall now call "definitions".
Adultery (Man) - A man commits adultery when he has sexual intercourse with a woman who belongs to another man.
Adultery (Woman) - A woman commits adultery if she is the woman of one man and has sexual intercourse with another man.
Fornication - Any act of sexual intercourse between two people who do not have a lifetime commitment to each other. The lifetime commitment is generally expected to be marriage, but may also include a concubinal relationship.
Another definition which I have come up with, based on studies less in depth than the above, but nevertheless I believe are in accordance with scriptural teaching, is of the word "concubine".
The word "concubine" in many countries refers to a woman who is taken in addition to the legal wife, or wives. It is often a secret arrangement. The term "mistress" is the same. It is understood to be a permanent relationship. Some countries offer limited legal protection for the concubine, but not as much as the wife enjoys.
In the Bible, the relationship was the same as just described, but with the exception that it was public knowledge, not a secret arrangement. Although God did not promote the practice, neither did he condemn it. It was a lifetime relationship. The woman is not called his "wife", but the man is called her "husband".
The discussion of the term "concubine" in this work uses the above definition. It does NOT refer to an adulterous relationship by the above definition of adultery.
Walter R. Sanchez