(All quotations taken from the Complete works of Swami Vivekananda (Vol. I-VIII)).
Millions massacred through Mohammad’s teachings : If you read the Koran, you find the most wonderful truths mixed with superstitions. How will you explain it? That man (Prophet Mohammed) was inspired, no doubt, but the inspiration was as it were, stumbled upon. He was not a trained Yogi, and did not know the reason of what he was doing. Think of the good Mohammed did to the world, and think of the great evil that has been done through his fanaticism ! Think of the millions massacred through his teachings, mothers bereft of their children, children made orphans, whole countries destroyed, millions upon millions of people killed ! (Vol. I. P. 184)
Muslim rituals : The Mohammedan, who thinks that every ritual, every form, every image or ceremony used by a non-Mohammedan is sinful does not think so when he comes to his own shrine, the Caaba. Every religious Mohammedan, wherever he prays, must imagine that he is standing before the Caaba. When the makes a pilgrimage there, he must kiss the black stone in the wall of the shrine. All the kisses that have been imprinted on that stone, by millions and millions of pilgrims, will stand up as witnesses for the benefit of the faithful on the Last Day of Judgment. Then, there is the well of Zimzim. Mohammedans believe that whoever draws a little water out of that well will have sins pardoned, and he will, after the Day of Resurrection, have a fresh body, and live for ever. (Vol. 2, p. 39)
Kill who are not Muslims : The Mohammedan religion allows Mohammedans to kill all who are not of their religion. It is clearly stated in the Koran, “Kill the infidels if they do not become Mohamedans”. They must be put to fire and sword. (Vol. 2, p. 335)
Killing unbelievers is surest way to Heaven : The more selfish a man, the more immoral he is. And so also with the race. That race which is bound down to itself has been the most cruel and the most wicked in the whole world. There has not been a religion that has clung to this dualism more than that founded by the Prophet of Arabia, and there has not been a religion which has shed so much blood, and been so cruel to other man. In the Kuran there is the doctrine that a man who does not believe these teachings should be killed; it is a mercy to kill him ! And the surest way to get to heaven, where there are beautiful ‘houris’ and all sorts of sense-enjoyments, is by killing these unbelievers. Think of the bloodshed there has been in consequence of such beliefs ! (Vol. 2, p. 352-53)
Every step forward was made with the sword : Think of little sects, born within a few hundred years out of fallible human brains, making this arrogant claim of knowledge of the whole of God’s infinite truth ! Think of the arrogance of it ! If it shows anything, it is this : how vain human beings are. And it is no wonder that such claims have always failed, and, by the mercy of the Lord, are always destined to fall. In this line, the Mohammedans were the best off; every step forward was made with the sword – the Koran in the one hand and the sword in the other : “Take the Koran, or you must die; there is no alternative !”. You know from history how phenomenal was their success; for six hundred years nothing could resist them, and then there came a time when they had to cry halt. So will be with other religions if they follow the same methods. (Vol. 2, pp. 369-70).
Universal brotherhood for Muslims only : Mohammedans talk of universal brotherhood, but what comes out of that in reality? Why, anybody who is not a Mohammedan will not be admitted into the brotherhood; he will more likely have his throat cut. (Vol. 2, p. 80)
Use of graves in place of images : The Mohammedans use the graves of their saints and martyrs almost in the place of images. (Vol. 3, p. 61)
God as a child : For the Mohammedans, it is impossible to have this idea of God as a child; they will shrink from it with a kind of horror. But the Christian and the Hindu can realize it easily because they have the baby Jesus and the baby Krishna. (Vol. 3, p. 96)
No temple building in a Muslim country : It is here that Indians build temples for Mohammedans and Christians; nowhere else. If you go to other countries and ask Mohammedans or people of other religions to build a temple for you, see how they will help. They will instead try to break down your temple and you too, if they can. (Vol. 3, p. 114).
Word Hindu covers all those who live in India : The word (‘Hindu’), therefore, covers not only Hindus proper, but Mohammedans, Christians, Jains and other people who live in India. (Vol. 3, p. 110).
Allah-ho-Akbar for centuries : Wave after wave of barbarian conquest has rolled over this devoted land of ours. “Allah-ho-Akbar !” has rent the skies for hundreds of years, and no Hindu knew what moment would be his last. This is the most suffering and the most subjugated of all the historic lands in the world. Yet we still stand practically the same race, ready to face difficulties again and again, if necessary, and not only so, of late there have been signs that we are not only strong but ready to go out, for the sign of life is expansion. (Vol. 3, p. 369-70).
Only they are right ! : Ignorant persons… not only deny the right of every man to interpret the universe according to his own light, but dare to say that others are entirely wrong, and they alone are right. If they are opposed, they begin to fight. They say that they will kill any man who does not believe as they believe, and as the Mohammedans do. (Vol. 4, p. 52).
Worshipping saints : The Mohammedans from the beginning stood against any idol worship. They would have nothing to do with worshipping the Prophets or the Messengers, or paying any homage to them; but, practically, instead of one Prophet, thousands upon thousands of saints are being worshipped. (Vol. 4, p. 121)
Mohammedans most sectarian : Now, some Mohammedans are the crudest in this respect, and the most sectarian. Their watchword is. “There is one God, and Mohammed is His Prophet”. Everything beyond that not only is bad, but must be destroyed forthwith; at moment’s notice, every man or woman, who does not exactly believe in that, must be killed; everything that does not belong to this worship must be killed; everything that does not belong to this worship must be immediately broken; every book that teaches anything else must be burnt. From the Pacific to the Atlantic, for five hundred years, blood ran all over the world. That is Mohammedanism ! Nevertheless, among these Mohammedans, wherever there was a philosophic man, he was sure to protest against these cruelties. (Vol. 4, p. 126)
Sword flashed for hundreds of years in India : Wave after wave had flooded this land, breaking and crushing everything for hundreds of years. The sword has flashed, and “Victory unto Allah” had rent the skies of India; but these floods subsided, leaving the national ideals unchanged. (Vol. 4, p. 159)
Kafir deserves to be butchered : To the Mussulmans, the Jews or the Christians are not object of extreme detestation; they are, at the worst, men of little faith. But not so the Hindu. According to him, the Hindu is idolatrous, the hateful Kafir; hence in this life he deserves to be butchered; and in the next, eternal hell is in store for him. The utmost the Mussulman kings could do as a favour to the (Hindu) priestly class – the spiritual guides of these Kafirs – was to allow them somehow to pass their life silently and wait for, the last moment. This was again sometimes considered too much kindness! If the religious ardour of any (Muslim) king was a little more uncommon, there would immediately follow arrangements for a great yajna by way of Kafir slaughter! (Vol. 4, p. 446)
Mohammedans brought murder here : You know that the Hindu religion never persecutes. It is the land where all sects may live in peace and amity. The Mohammedans brought murder and slaughter in their train, but until their arrival peace prevailed (Vo. 5, p. 190)
In India the Mohammedans were the first who ever took the sword. (Vol. 5, p. 197)
Loss of a Hindu, gain of an enemy : When the Mohammedans first came, we are said – I think the authority of Ferishta, the oldest Mohammedan historian – to have been six hundred millions of Hindus. Now [i.e. in 1899 AD] we are about two hundred millions. And then every man going out of the Hindu pale is not only a man less, but an enemy the more.
Again, the vast majority of Hindu converts to Islam and Christianity are perverts by sword, or the descendants of these.” (Vol. 5, p. 233)
Mohammedan conquest had to fall back : The wave of Mohammedan conquest, which had swallowed the whole earth, had to fall back before India. (Vol. 5, p. 528)
Hashashin became ‘assassin’ : Hashshashin has became our word ‘assassin’ because an old sect of Mohammedanism killed non-believers as a part of its creed. (Vol. 7, p. 40)
Islam caused great violence : The Mohammedans used the greatest violence. (Vol. 7, p. 217).