“I am only human, although I regret it.”

His last letter, to Myron Benton (31 March 1862) http://www.walden.org/Institute/thoreau/writings/correspondence/1862_03_21_Benton.htm
Context: You ask particularly after my health. I suppose that I have not many months to live; but, of course, I know nothing about it. I may add that I am enjoying existence as much as ever, and regret nothing.

Source: Dreams Made Flesh

Source: Love in the Time of Cholera

On reactions to his spray painting the fountain at the free concert he gave in San Francisco, in a Press conference (November 1987) http://www.u2source.com/2007/08/19/bono-press-conference-regarding-graffiti/
Context: It is fair to say that we overreacted a bit. … Its not really worth defending my action, I did it in the spirit of the concert, and I thought I did it in the spirit of the artist's work, and he agreed — but, in fact he didn't own his work anymore, as most artists are prone to, he'd sold it, and the City of San Francisco owned it, and they didn't like what I did at all. … Its a really wild thing, you know, you're in Rock n Roll band — you know, I happen to sell millions of records — people therefore think that makes you a responsible citizen — this is not true. … I think this is one of the more mild actions of tour-madness. … It's the music that is magical with U2. … I don't mind being arrested for putting on a free concert, but I don't want to be arrested for being a vandal. I am a vandal and I do regret what I did. I really do regret it. It was dumb.

Deathbed assertion, as quoted in Outlook Business, Vol. 3, No. 4 (23 February 2008)

Source: Where Angels Fear to Tread