Fornication, Celibacy, and chastity

Well the title may grab your attention!
A respondent to a former entry about celibacy (see here) asks why I assert that Christians are called to be chaste!
Let me try to begin some discussion on this.
Language
It needs to be said that language is in a state of constant change, and the formerly infrequently used words "chastity" and "celibacy" (particularly the latter) have in latter times taken on a life in popular culture which a decade ago they didn't have.
Celibacy, a word, until recently, almost exclusively reserved for the world of religion is now used to address the lives of young people who choose, to refrain from having sex.
It is now in popular usage, and probably popular culture is more engaged with this group of people than with the issue of whether or not certain religious officials are required to remain unmarried.
In previous usage I would have thought this decision to abstain was actually what we call "chastity".
This word, too, in my mind, has had a change of meaning.
It used to refer to single people choosing to abstain from sex, but now has a wider meaning (see here for example) as per this definition: " not having had sex, or only having a sexual relationship with the person whom you are married to".
In this latter sense I responded that married people are called to be chaste, but obviously they are not celibate, and they may and do have sex!
My point is not so much to narrowly define the words but to recognise that the language of relationship is fluid and changing. We can talk about relationships with gay abandon! But even that innocent expression means something different now than it meant to my father who died over 20 years ago
Chastity
"Can you explain," my respondent asked,"why we are called to be chaste?"
This is, of course, a good question and it deserves proper attention.My short answer is:
......

there is a complex of influences that need to be brought to bear on such issues, these include:
the scriptural witness
the tradition and teaching of the church
personal experience
and individual conscience.

To rely on just one of these is to ask for problems and distortion...

I sense a treatise coming on......
There would seem to me little doubt that the Judaeo-Christian tradition, drawn from the Bible and as put into practice by Christians for 2000 years understands that the proper place for sex is in committed one-to-one relationships. [I don't wish to get into same-sex relationships here, but it seems to me that this possibility is not discussed by the scriptures...but same sex immorality is condemned, as indeed different sex immorality is too!]
There is no doubt that this is a high standard and we struggle with it. At times we fail spectacularly...those Borgia Popes you know!....
What I also note is that my personal experience is congruent with this. And I suggest that most Christians would agree with that. In the end, sex is an important thing, it is not neutral or meaningless it is, in fact, charged with meaning and powerfully influential.
You do not have sex with someone as though it is "recreation" and then walk away as though we have not been affected.
Much of our media portray sex in this sort of way, but I think it is just not true. I actually think a case could be made to suggest that "casual sex" is a myth put about by men...who do not understand that women are not from Mars...nor do they think that sex is "casual".
My experience tells me that sex is important, and never without consequence.
This is, I think, quite consistent with the traditional scriptural teaching about chastity and the understanding and teaching of the church.
Conscience
Finally, in the end our consciences must inform what we do. The great theologian, Thomas Aquinas, tells us that "The one who acts against their conscience always sins".
Let us not think we are given a rule book and told to go out and obey the rules. In one sense that is the very opposite of Christianity.
We are adults destined to exercise free-will.
St Paul tells us

It is for freedom that Christ has set us free. Stand firm, then, and do not let yourselves be burdened again by the a yoke of slavery (Galatians 5:1)

This is, for me, the core of the work of Christ. But so often we like to be treated as though we are less than this, and/or to treat others without the respect that this grants them.
Like all, complex issues, conscience and freedom require that we grapple with the difficulty of these issues for ourselves.....and not merely conform to the rule book.
What, I guess, I have offered you is some of my grappling with this issue.