A lecture presenting this article,[18] and in particular comments Brown made during the Q&A session, sparked criticism from a number of conservative commentators, some of whom accused Brown of supporting slavery and rape.[19][20][21] In addition, some liberal scholars of Islam criticized Brown for relativizing the concepts of slavery, human autonomy, and consent, and took issue with his suggestion that Muslims cannot view all historical forms of slavery to be immoral since the Islamic prophet Muhammad had owned slaves.[19]