If a Muslim and a dhimmi (non-Muslim under protection) are together in a public bath, the Muslim should wash from the pool before the dhimmi. It is not permissible to purify with leftover water of the public bath, as it includes the washings of Jews, Zoroastrians, Christians, and those who harbor enmity toward the family of Muhammad عليه السلام, the last of whom are the worst of them.
Commentary #8