A lecture delivered in Arabic at the Prophetic Mosque at the presence of the Moroccan King Muhammad, the fifth. It is later translated to be in Vietnamese book. The lecturer explained the Quranic verse, "This day those who disbelieve have despaired of [defeating] your religion; so fear them not, but fear Me. This day I have perfected for you your religion and completed My favor upon you and have approved for you Islam as religion." He confirmed that Islam completely and perfectly dealt with all matters that humankind concerns. Afterward, he discussed some topics as Islamic monotheism, righteous vs. bad acts, Muslim society, and the problem of Muslims' weakness.