What was the passing act of kindness Jaime Lannister believes he was loved for?

Question

I believe it was in A Storm of Swords, during one of Jaime Lannister's POV chapters he muses that he is loved for:

a passing kindness he never committed and hated for his greatest act...

I am paraphrasing, these are not direct quotes. I believe his greatest act was killing the Mad King and saving King's Landing from death by fire, but what was the 'passing kindness' he was loved for?

Answer 1

The quote is:

"I think it passing odd that I am loved by one for a kindness I never did, and reviled by so many for my finest act."

^{A Clash of Kings, Catelyn VII}

The explanation holds a spoiler for those who have not finished A Storm of Swords:

Jaime is talking about the incident with Tysha and Tyrion. Tyrion thinks that Jaime secretly bought him Tysha so that he can lose his virginity, and while the incident ended badly Tyrion thought the world of Jaime despite of it. But the bitter truth (that Jaime is hiding) is that Tysha was not a prostitute and was exactly who she said she was. Jaime hates himself for lying to Tyrion about this fact.

Answer 2

I don't know what this quote is referring to, but I'm hard-pressed to believe he's referring to Tyrion and Tysha. It's a relatively suitable explanation, I suppose, but I think he's talking about a Stark. Who, and for what reason, I do not know, but the entire conversation leading up to this statement was about Starks.

Jaime is telling Catelyn how Brandon and Rickard die. Catelyn thinks Jaime is trying to claim that he killed Aerys to avenge Brandon Stark, and Jaime says:

"I made no such claim. The Starks are nothing to me. I will say, I find it passing odd that I am loved by one for a kindness I never did, and reviled by so many for my finest act."

When I read this statement, I took him to be saying, "I find it passing odd that I am loved by one [Stark] for a kindness I never did, and reviled by so many [Starks] for my finest act."

I do not know which Stark he is referring to, but I lean most toward Lyanna, followed by Brandon or Rickard. We know Ned and Catelyn don't like him, and other than Bran's vague disquiet, none of the other Starks have any feelings toward him. He's not even on Arya's kill list.

I don't think it's referring to Tyrion and Tysha for the following reasons:

1. The statement seems to imply Starks, given the sentence preceding it.
2. Tyrion never expresses gratitude for this supposed kindness. In fact, Tyrion is heart-broken to learn the supposed truth of Tysha. Tyrion grows up tormented by his perceived misplaced affection for a whore, and questions his ability to be loved.
3. The "loved him for a lie" quote that is often attached to Jaime's quote to lend credibility to the argument doesn't really fit. Tyrion doesn't love Jaime because Jaime lied about Tysha being a whore. Jaime feels guilty about hiding the truth from Tyrion, and Jaime is worried that Tyrion's love for him hinges on the truth about Tysha.

Answer 3

I think he is referring to the event described in Storm of Swords. He does not say it was a "passing act of kindness" (the OP has misquoted there). He says he finds it "passing odd" that he is loved for it. And it is odd. Tyrion loves Jaime because he thinks he opened his experience to the only kind of women who will ever love him: professional sex workers. He is grateful to Jaime for opening this pleasure to him, thinking he can never get anything more. What he does not yet realise is that Jaime closed a door, not opened one. When Jaime confesses the truth in SoS Tyrion is not best pleased with his brother.