I read many of your very fine Q&A, articles, and sermons on your web site. Your candor is refreshing as well as offering much.
We are searching for conclusions on how to address one aspect of the sexual immorality subject and, perhaps, your study of the subject might help us shed some light on how to approach it.
The usual list of transgressions that require some form of intense teaching or discipline includes sexual immorality (porneia). A problem that came up in discussion, here, is how to define it relative to the unmarried elderly who are in reasonably serious relationships. If we take Vine's, for example, it gives only "sexual intercourse." That's very narrow in possible acts that can occur and may be inconclusive but we're not sure.
If I correctly understand your writings, we should correctly teach that any kissing (other than pecks) and hugging must be avoided. That would be the conclusion of the group since they would know that these actions inevitably lead to other physical activity no matter how innocent the beginning since that is human nature. They are savvy enough to know this for sure and, sadly, I agree. I'm also fairly certain that the response would be laughter in that it lacks any reality and is akin to the prohibition age.
We don't uniformly know how to respond to this and would be most appreciative of any scripturally-based assessment on this issue.
The Greek word porneia refers to immoral sexual acts of any sort; this would include sexual intercourse, oral sex, and foreplay that leads up to sex. Or, to be extremely blunt, porneia are those acts which can bring about an orgasmic response in another person. These acts done outside the context of a husband and wife relationship are forbidden in the Scriptures (Hebrews 13:4; I Corinthians 6:9-10).
Kissing and hugging, in and of themselves, would not be wrong. One can kiss a child goodnight or give an aunt a hug in greeting with nothing sexual intended or thought about. However, we all know that extended kissing or hugging can bring about a sexual response between a man and a woman. I believe that the reason you are running into difficulty is that you are lumping too much into the category of porneia. There are other terms which better define what is wrong and why it is wrong.
The first is lust (epithumeo in the Greek). This is the word for a strong desire. As the word "lust" in English, the word technically means any strong desire, but it most of the time it refers to a strong desire for that which is illegitimate for a person to have. Jesus stated, "But I say to you that whoever looks at a woman to lust for her has already committed adultery with her in his heart" (Matthew 5:28). Thus, even though an improper action has not taken place, the thoughts of doing an improper action are stated to be equivalent. Thinking about having sex with someone to whom you are not married is just as sinful as actually committing the act. The only difference is the lack of opportunity. Therefore, doing or thinking things that inflame a desire to commit a sin is wrong.
The second word is passion (pathos in the Greek). It refers to sexual desires that are difficult to resist. "Therefore put to death your members which are on the earth: fornication, uncleanness, passion, evil desire, and covetousness, which is idolatry" (Colossians 3:5). In this word would include those things used to arouse sexual responses, such as pornography or the wearing of skimpy clothing. "For this is the will of God, your sanctification: that you should abstain from sexual immorality; that each of you should know how to possess his own vessel in sanctification and honor, not in passion of lust, like the Gentiles who do not know God" (I Thessalonians 4:3-5).
The third word is the hardest to define precisely, but it should not be ignored. The word is uncleanness (akatharsiain the Greek). It refers to things that are morally impure or things that dirty the mind. "But fornication and all uncleanness or covetousness, let it not even be named among you, as is fitting for saints; neither filthiness, nor foolish talking, nor coarse jesting, which are not fitting, but rather giving of thanks. For this you know, that no fornicator, unclean person, nor covetous man, who is an idolater, has any inheritance in the kingdom of Christ and God" (Ephesians 5:3-5). Dirty jokes, sexually charged innuendos, and the like are things in which it is not proper for Christians to participate. We must show a separation for the world pursuit of sexual gratification not only in our deeds but also in the way we speak.
In dealing with the elderly we often dismiss sexual sins out of hand. "They're too old." Just as teenagers cringe at the thoughts that their parents might engage in sex, we retain that same mental block toward people older than ourselves. But as most older people can tell you, libido may diminish, but it never goes away unless a person has a physical problem. Just because a person is in the winter of their life, it doesn't mean he can ignore sexual temptations. "Therefore let him who thinks he stands take heed lest he fall" (I Corinthians 10:12).
As we move toward the waning years of life, it is very common for one spouse to die before the other. This leaves the one behind lonely and yearning for companionship, but often they have made financial arrangements that would become difficult if they married again. Thus we face a growing number of elderly people moving in together for the convenience of the companionship, but not bothering with marriage so as to preserve the inheritance of their children and grandchildren. However, step back and look at the situation unemotionally and see that people are justifying committing fornication or giving the appearance that fornication is being committed all for the sake of greed! Since when has money ever altered morality?
Then, too, the elderly need to consider the example they are setting for the young. If it is alright for grandma to have a male companion in her home, then how can anything be said to the eighteen-year-old who wants to move in with her boyfriend? "But as for you, speak the things which are proper for sound doctrine: that the older men be sober, reverent, temperate, sound in faith, in love, in patience; the older women likewise, that they be reverent in behavior, not slanderers, not given to much wine, teachers of good things-- that they admonish the young women to love their husbands, to love their children, to be discreet, chaste, homemakers, good, obedient to their own husbands, that the word of God may not be blasphemed" (Titus 2:1-5).
If an elderly person desires companionship, then he ought to consider marriage. If there are financial concerns, well, that is why we have wills. But never should we seek excuses for sin.