In our saga, a young noblewoman's True Love is an impoverished knight, who is completely below her station. Instead, her family has arranged a political marriage for her with a neighbouring noble. This is certainly the best possible match for the good of the land, as it will cement the peace and increase the prosperity of the two fiefs. Note that the groom is by no means a bad guy, he just isn't her True Love.
The noblewoman is a very, very pious Christian (she has True Faith). She would never consider eloping with the knight unless married to him. So, on the eve of the wedding, she is considering three options:
Run away to marry her True Love and live a simple life with him in some faraway land.
Marry as directed by her family and become a devoted wife to a man she does not love, while harbouring in her heart (only!) the secret of her True Love.
Become a nun.
Not knowing what to choose, she is praying for God's guidance. It falls to the Storyguide to answer her prayer. In medieval sensibilities, which would be the most Christian course of action among the three above? Or perhaps there's a fourth choice neither I nor her have considered?
A demon tempts her to commit suicide? Obviously this would exit the character from the saga (I think the nun option does, too), but if you have any infernal influences planned, and the player isn't wanting to play the character after being married to the noble could be an option.
Is the knight a PC? The knight could be plagued by the same demon with the fact that he caused the death of his True Love. Or if an NPC, he could be convinced by the demon that those magi she consorted with somehow caused her to commit suicide.
Or she marries the noble and in a few years he and her true love die in some crusade or something...
If 2, because she is very pious, she would presumably feel terribly guilty about the fact that her "True Love" is not her husband, and will need to frequently confess and take penance for her inappropriate thoughts. So, it probably wouldn't be a secret kept (for long, anyway) from her confession priest. Her confession priest might leak this information (or she might merely be overheard in confession) which could create future story strife. The priest is not meant to leak confessions, of course, but he's human.
If 3, because this is a political marriage arranged by a noble family, there is a good chance that they will fetch her from the nunnery and convince/force her to follow through on the marriage (i.e. future story opportunity). A nunnery is not a high security facility, where she can indefinitely hide from the world.
I'm going with option 4... trust that God has a plan.
Running off with him would be betraying her father and throwing the land into turmoil - bad. Marrying the man who is not her True Love would be denying the divine blessing that is that love - bad. Hiding in a convent is nothing more than running away from both her love and her duty - worst option of all.
I don't think that God (in the person of the storyguide and of the story) would/should truely demand that she be forever seperated from her True Love... because True Love is a holy thing. Circumstances (which is to say a big crazy story) should ultimately bring her together with her True Love... no doubt in a way that will ultimately serve an even greater good then her prospective marriage... but not until both have faced trials and dangers to test their love and her faith.
I suggest she should go ahead with the marriage... but circumstances should prevent it from actually happening. Adventures and stories should ensue. Her True Love should achieve some great deed that helps bring peace and prosperity (or serves some other holy purpose) and causes him to gain status and wealth enough to be worthy of her (with lots of help from whatever PCs are involved in all this) and finally the two should be married, with the blessing of her father and present betrothed and to the good of all the land.
A Good christian woman should "obey her husband" and "obey her father". Rebellion against authority came much later. That rules out #1.
If she has carnal desires for her True Love and believes it is a sin, she may wish to retire to a nunnery until the Lord offers her guidance. That allows #3 for as long as it takes, and can be done after marriage too.
If she can keep it as courtly love, then she can be true to her husband and follow fashion.
Please note that I'm not asking which is the most "pragmatic" option. Nor am I asking which option is the one that will lead to better stories. I'm asking what would be the most Christian option in medieval sensibilities.
The problems with each choice, in this perspective, are the following.
Run away and marry the knight. Problem: this means forfeiting her duty to her land and family.
Being the dutiful but loveless wife of the nobleman. Problem: is it right (i.e. fair to everyone else, including God) to marry someone whom you know you will never love, because your True Love (which is not just love, it's something ordained in Heaven) is someone else?
Becoming a nun. Problem: although this seems a "morally safe" choice, is it really pious to become a nun not for the love of God but to avoid choosing between duty and True Love?
Personally, I'm inclined to go with 2. Looking at old Christian marriage vows, it seems the word "love" was introduced only pretty recently. So I do not think it would be un-christian to love someone other than one's husband, as long as bridal vows are not violated. Which will be far more difficult, but in some sense can be seen as a (really, really harsh) Test of Faith: live a life as a faithful wife (good), for the good of the land (also good), chastely loving someone other than your husband (dangerous and painful, but not intrinsecally bad).
Incidentally, I do not think un-chaste thoughts are inherently sinful (according to medieval Christian sensibilities), if one promptly chases them away and does not act or linger on them. Being tempted is not sinful.
Of course, whatever works for your saga is fine, but medieval thought does seem to be that imagined as well as enacted sins counted. This interpretation seems to ultimately derive from the 10th commandment (do not covert thy neighbour's wife, ox, etc).
Anyway, even if a lesser mortal would find this debatable, this character is supposedly a "very, very pious Christian". Such a character is surely going to find "being tempted to sin" something worthy of confession (even if quantitatively less sinful than an actual act).
A truly pious person doesn't ask God what the plan is... a pious person has Faith that God has a plan and trusts that things will unfold in accordance with that plan.
If what she is asking is "God, what should I do that is in accord with Your plan" then the right answer is whichever action the storyguide, in his or her role as God, feels leads best to the next part of the story... and forget about what medieval Christian thought says about it because, in Ars Magica, God isn't Christian (otherwise the other faiths wouldn't generate Divine auras).
As far as I know, in medieval thought there's a subtle but crucial distinction between actively lingering on an imagined sin, and chasing it away as soon as the possibility presents itself to one's mind. The former is a sin, albeit a lesser one (as you correctly argue, because of the 9th and 10th commandments). But the latter isn't. If it were, any temptation would automatically be a sin. This would go against the notion of "test of faith": to be tested, one has to contemplate the possibility of sinning, and reject it.
More precisely, she's asking what is the most virtuous choice. In theory, that should be self-evident (after all one is supposed to know good from evil). But she's confused, so she is praying to be shown how she can avoid sinning.
God could certainly answer "you know, the right thing would be X, but in this case trust me and do Y, I know what's best" (think of Isaac's sacrifice). However, I'm interested in X, rather than Y.
I'm not sure if that is the kind of theological/legal contortion that a pious layperson would apply. Wouldn't a pious layperson confess and accept the priest's judgement on whether and what sort of sin she had committed? Wouldn't she humbly defer to the priest's judgement rather than run the risk of committing the sin of pride in her own theological arguments?
Anyway this distinction, if it exists, would only seem to apply to a one-time-thought of sin, which was then promptly and primly resisted. However, realistically in this situation the noblewoman is going to have on-going, recurring thoughts that she would much rather be married to her "True Love". How many times does she have to deny the same thoughts of the same sin before she counts as "actively lingering"? This seems to be exactly the set-up for a cycle of confession and penance.
See, I don't think that God would say that at all. Not that I think God would say anything so clear... but I do think God would simply "say" do Y... because Y will be both virtuous and right, because God is God and can't suggest anything that would be otherwise.
Sure ... what I keep trying to say, is that I want to know what is the virtuous choice under the situation as presented.
In other words, the answer she would get if she asked counsel to another very pious person who could not see God's plan rather than to God directly.
That's quite different from what you originally asked! If the noblewoman's family isn't wicked or otherwise tainted with sin, a pious man would instruct her to go along with her family's (father's) wishes and marry the other noble, for it is a daughter's duty to follow her father's instructions, and then, when married, her husband's.
If the father is wicked, and the knight especially virtuous, there might be an argument to be made.
I really do not think it's a "thelogical/legal contortion". Every Christian knows that countless saints were tempted, that the angels were tempted, that even Christ was tempted. Being tempted is not a sin. Acting on a temptation, or actively phantasizing on it, is a sin.
No. It's not an issue of frequency. It's the same difference between seeing and watching. You do not choose to see. You choose to watch. You can see something a thousand times, and if you avert your eyes every time, you've never watched it. The fact that temptation is recurring makes it more difficult to resist, but makes resistance all the more virtuous.
Being tempted isn't a sin, but coveting somebody else's wife (and probably husband) is.
The entirety of the situation (being deeply, albeit chastely, in love with somebody other than your husband, and whom you would have much rather married than your husband) seems dubious enough that a genuinely pious woman would confess or at least ask her priest for further guidance on whether she was comitting a sin.
Certainly, a non-pious character would probably think nothing much of it. However, if the noblewoman is "very very pious" she is not going to satisfied with upholding the barest minimum of Good Christian standards.
This option has become acceptable only very recently.
Many traditional faerie tales can be argued to be a warning against doing this.
The only argument in favour of this one, is that the love is True.
This is the one favoured by the church of the times. In the north she would simply be expected to suck it up and ignore her "youthful fancy" while in the south she woul probably be expected to play by the rules of courtly love. After all, the poets did not equate love and marriage
This is where things become interesting. This choice looks good (indeed unassailable) at first glance, but it violates the True Love (probably) as well as duty. I've seen it argued that women had the right to dedicate themselves to God only after becomming widows, though I have no idea how widely this view has been held historially.
By medieval sensibilities I'd have to agree, epecially the Test of Faith thing.