This book is a collection of six speeches delivered by Sayyid Ali Khamenei on the topic of Tawhid in the month of Ramadan 1971 at Masjid Imam Hasan (‘a) in Mashhad, Iran. Sayyid Khamenei talks about the Islamic vision of the universe where every existence is linked to a powerful creator and this power or omnipotence is God. He has all the basic good attributes such as knowledge, control, will, life etc. From the smallest particle to the heavens, moon, stars and unknown galaxies, everything is in His control. Every reality in the universe, human beings and others owe their creation and life to Him and are His slaves and servants.