The Holy Quran mentions the blind beliefs of the nation of Thamud that out of fear of hunger and thirst they rejected the bounty of Almighty Allah. That dromedary that had been sent to them as a sign of Allah’s power, they slaughtered that dromedary, kept on disobeying Almighty Allah and because of this, they were punished. They were not prepared to let Hadhrat Saleh (May peace be upon him) and his followers to even stay with them. They told him that we consider you and your followers as inauspicious that this difficulty has come on us because of you. It is given in the Holy Quran:
They said: ?You have caused us misfortune, and so have your companions.? (Salih) said: ?(The cause of) your misfortune is (written) with Allah; you people have rather been put to trial.? Surah Naml (27:47)
This verse of the Holy Quran shows us that difficulties are a result on one’s own deeds. Holding others responsible for them is not the practice of Muslims. It is in fact the practice of those who deny Allah, as mentioned in this verse of the Holy Quran:
And whatever misfortune befalls you (comes upon you) as a result of that (evil work) which your own hands have done whilst He forgives most of your (misdoings). Surah Shoora (42:30)
As far as taking an ill omen is considered, the Holy Prophet (Sallallahu alaihi wa sallam) has declared this very belief as wrong and negated it in the following words:
Translation: It is narrated on the authority of Hadhrat ‘Abdullah bin Mas’ud (May Allah be well pleased with him) that the Holy Prophet (Sallallahu alaihi wa sallam) said: Taking an ill omen is similar to polytheism. He repeated this thrice. (Jame’ Tirmidhi, Hadith No. 1712; Sunan Abu Dawood, Hadith No. 3912)
Hadhrat Mulla ‘Ali Qari (May Allah shower His mercy on him) writes in the interpretation of this Hadith:
Translation: Taking something as an ill omen is Shirk (associating things with Allah), as in the pre-Islamic days, people used to believe that by acceding to the demand of an ill omen, they will receive some benefit or that it removes some hardship or difficulty and if they accede to that demand then it is as if they have ascribed partners to Allah and this is called Hidden Polytheism (Shirk Khafi) and if a person holds the belief that there is something other than Allah which can benefit and harm, which has its own power, then they have committed Blatant Polytheism (Shirk Jali). (Mirqaat Ul Mafateeh Sharh Mishkaat Ul Masabeeh, Vol. 4, Pg. No. 522)
‘Allama Qazi Iyaz (May Allah shower His mercy on him) says:
Translation: The Holy Prophet (Sallallahu alaihi wa sallam) declared this as polytheism because those kind of people believe that that thing from which they take the ill omen has the power to affect and acceding to these things is generally Hidden Polytheism, especially when ignorance and blind beliefs are also present, then it is all the more obvious why this is Hidden Polytheism. (Mirqaat Ul Mafateeh, Vol. 4, Pg. No. 522/523)
There is another Hadith in Sunan Abu Dawood:
Translation: Drawing omens using birds, taking something as ill omen and drawing omens using pebbles are all satanic activities. (Sunan Abu Dawood, Hadith No. 3909)