Now and then she helped herself to something or other out of the King's private property, it mattered not what it was, to give to a poor person; and this pious plundering the King always took pleasantly and in good part. It was his custom to offer certain coins of gold upon Maundy Thursday and at High Mass, some of which coins the Queen often devoutly pillaged, and bestowed on the beggar who was petitioning her for help. Although the King was fully aware of the theft, he generally pretended to know nothing of it, and felt much amused by it. Now and then he caught the Queen in the very act, with the money in her hand, and laughingly threatened that he would have her arrested, tried, and found guilty.
Although [Malcolm] could not read, he would turn over and examine books which she used either for her devotions or her study; and whenever he heard her say that she was fonder of one of them than the others, this one he too used to look at with special affection, kissing it, and often taking it into his hands. Sometimes he sent for a worker in precious metals, whom he commanded to ornament that volume with gold and gems, and when the work was finished, the king himself used to carry the volume to the queen as a kind proof of his devotion.
Why, no, I am not endlessly attracted by stories of people who lead their spouses to holiness; why do you ask?
Here's a fun fact related to what I'm currently working on (look away now if you don't enjoy pointless chatter about medieval genealogy): Margaret's son David married Matilda, the daughter of Waltheof. Since I have been doing little but think about Waltheof lately, this fact never ceases to entertain me. It's fun to work out the implications. First of all, it meant that the children of David and Matilda had two saints among their four grandparents (both Margaret and Waltheof were dead by the time of their children's marriage, which took place in 1114). That's pretty cool, even before you factor in Edward the Confessor and the various saints of Wessex among Margaret's ancestors, and the fact that one of Matilda's sons by her first marriage became a saint too.
Secondly: Waltheof was executed for treason by William the Conqueror. But his son-in-law David had a sister, Edith, who married the son of William; she was responsible for bringing the bloodline of the Anglo-Saxon kings back into the Norman line.
Thirdly: the only other place in England, apart from Crowland, where Waltheof was venerated as a saint was at Romsey Abbey in Hampshire (we know this because Anselm didn't approve of it, and wrote to the nuns telling them to cut it out). Margaret's sister was a nun at Romsey. So was Margaret's daughter Edith, for a bit (although, controversial...). Coincidence? I don't know.
Fourthly (I saved the best to last): because of this marriage, the present Queen is theoretically the direct descendant of a polar bear. Yes, really. Waltheof's grandfather claimed to be the son of a bear and a human woman (he had furry ears to prove it). Through the marriage of Waltheof's daughter, he (and the bear) became an ancestor of the kings of Scotland, from whom the current royal family are descended. I wonder if anyone's told the Queen this?