belief that there is only one god
Monotheism is the worship of one god.
- I am Jehovah, and there is no one else. There is no God except me. I will strengthen you, although you did not know me, in order that people may know from the rising of the sun to its setting that there is none besides me. I am Jehovah, and there is no one else.
- Say: He is Allah, the One and Only; Allah, the Eternal, Absolute; He begetteth not, nor is He begotten; And there is none like unto Him.
- שְׁמַע יִשְׂרָאֵל יְהוָה אֱלֹהֵינוּ יְהוָה אֶחָד.
- Πιστεύω εἰς ἕνα Θεόν, Πατέρα, Παντοκράτορα, ποιητὴν οὐρανοῦ καὶ γῆς, ὁρατῶν τε πάντων καὶ ἀοράτων.
- I believe in one God, the Father Almighty, Maker of Heaven and Earth, and of all things visible and invisible.
- Incipit of the Nicene Creed.
- أشهد أن لا إله إلا الله و أشهد أن محمد رسول الله.
- I testify that there is no god but Allah, and I testify that Muhammad is His Messenger.
- Ὁ δὲ Ἰησοῦς ἀπεκρίθη αὐτῷ ὅτι «Πρώτη πάντων τῶν ἐντολῶν, ‹Ἄκουε, Ἰσραήλ, Κύριος ὁ Θεὸς ἡµῶν, Κύριος εἷς ἐστίν›· 30καὶ ἀγαπήσεις κύριον τὸν Θεόν σου ἐξ ὅλης τῆς καρδίας σου, καὶ ἐξ ὅλης τῆς ψυχῆς σου, καὶ ἐξ ὅλης τῆς διανοίας σου, καὶ ἐξ ὅλης τῆς ἰσχύος σου. Αὕτη πρώτη ἐντολή».
- And Jesus answered him, “The first of all the commandments is, ‛Hear, O Israel: The Lord our God is one Lord,’ 30and thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind, and with all thy strength: this is the first commandment.”
- Bible, Mark 12:29-30, KJV
- Abraham was the first to teach the Unity of God, to establish the faith, to cause it to remain among coming generations, and to win his fellow-men to his doctrine; as Scripture says of him: "I know him, that he will command," &c. (Gen. xviii. 19)
- The chief rival to monotheism, I shall contend, is henotheism or that social faith which makes a finite society, whether cultural or religious, the object of trust as well as of loyalty and which tends to subvert even officially monotheistic institutions, such as the churches.
- H. Richard Niebuhr, Radical Monotheism and Western Culture (1960), p. 11
- Monotheistic religions alone furnish the spectacle of religious wars, religious persecutions, heretical tribunals, that breaking of idols and destruction of images of the gods, that razing of Indian temples and Egyptian colossi, which had looked on the sun 3,000 years: just because a jealous god had said, 'Thou shalt make no graven image.'
- Arthur Schopenhauer, On Religion.
- Monotheism occupies so large a space in the view of modern minds, that it is scarcely possible to form a just estimate of the preceding phases of the theological philosophy.
- As Christianity in its beginnings was surrounded by the polytheistic beliefs and practices of the pagan world, a clear and authoritative expression of Monotheism was necessary. Hence the symbols of faith, or creeds, open with the words: "I [we] believe in God"...(APOSTLES' CREED; ATHANASIAN CREED ; NICENE CREED.)
- Islam and Christianity share a common monotheistic vision: a belief in one divine God, in the transience of our earthly life, in our accountability for our actions, and in the assurance of life to come.
- In the footsteps of the reform movements Brahmo Samaj and Aryan Samaj, many anglicized Hindus claim that “Hinduism too is monotheistic”. This is a very defensive stand, and it is simply not correct. If the Hindu wealth of gods and of ways of worship were not polytheistic, what other religion would be? It seems to us that they are using a word they don’t understand. Monos does not mean “one”, it means “alone”, “one and no other”. Monotheism accepts only Yahweh or Allah, and considers all others as false gods, only good to be destroyed and discarded.
- The idea of God, Dr. Elst, K. 3 September 2016 
- I regard monotheism as the greatest disaster ever to befall the human race. I see no good in Judaism, Christianity, or Islam — good people, yes, but any religion based on a single... well, frenzied and virulent god, is not as useful to the human race as, say, Confucianism, which is not a religion but an ethical and educational system that has worked pretty well for twenty-five hundred years. So you see I am ecumenical in my dislike for the Book. But like it or not, the Book is there; and because of it people die; and the world is in danger.
- Gore Vidal, At Home (1988), Appendix
- The great unmentionable evil at the center of our culture is monotheism. From a barbaric Bronze Age text known as the Old Testament, three anti-human religions have evolved — Judaism, Christianity, Islam. These are sky-god religions. They are, literally, patriarchal — God is the Omnipotent Father — hence the loathing of women for 2,000 years in those countries afflicted by the sky-god and his earthly male delegates. The sky-god is a jealous god, of course. He requires total obedience from everyone on earth, as he is in place not for just one tribe but for all creation. Those who would reject him must be converted or killed for their own good. Ultimately, totalitarianism is the only sort of politics that can truly serve the sky-god's purpose.
- Gore Vidal. "America First? America Last? America at Last?", Lowell Lecture, Harvard University (20 April 1992)
- Monotheism. The Catholic Encyclopedia.