And it's this notion that a Muslim needs to believe and say that there is no God but God. Muhammad is God's messenger. And in fact, to convert to Islam, you need to say this and you have to say it in the presence of at least two witnesses. And that's all that's necessary in order to convert. Now the other key element of Islam, the second, you could say, of the five pillars, is this notion of prayer. So Muslims pray five times a day at dawn, noon, in the afternoon, evening, and night, and they face in the direction of the Kaaba, which is based in Mecca, which once again, they believe that Abraham constructed with his son Ishmael, who they believe that the Arab people are descendant from. Now what's interesting about this, this has a lot of parallels with the five times a day prayer of the Zoroastrians, including the ritual washing of your body before each prayer.