Tawus narrates from Sayyiduna Ibn Abbas (may Allah be pleased with them both), who said: Husayn asked my permission to set out (for Kufah). I said: Were it not that this would disgrace me or you, I would have entangled my hand in your head (hair). Ibn Abbas said: His reply to me was that he said: "That I be killed at such-and-such a place is dearer to me than that the sanctity of Allah and His Messenger be violated because of me." Ibn Abbas said: That was what set my mind at rest about him.
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2846