Who was it that Asma bint Abi Bakr (may Allah be pleased with them both) said about, "Indeed, the flaying of the ewe does not harm it after its slaughter," and why?

The aforementioned statement is attributed to Asma bint Abi Bakr Al-Siddiq, when she addressed her son Abdullah ibn Al-Zubayr, after he consulted her about fighting the soldiers of Al-Hajjaj ibn Yusuf, fearing that they would mutilate his body after killing him.