The word(s) "doubt" appears 83 time(s) in 77 verse(s) in Quran in Mohsin Khan translation.

(1) This is the Book (the Qur'an), whereof there is no doubt, a guidance to those who are Al-Muttaqun [the pious believers of Islamic Monotheism who fear Allah much (abstain from all kinds of sins and evil deeds which He has forbidden) and love Allah much (perform all kinds of good deeds which He has ordained)].

(2) In their hearts is a disease (of doubt and hypocrisy) and Allah has increased their disease. A painful torment is theirs because they used to tell lies.

(3) And if you (Arab pagans, Jews, and Christians) are in doubt concerning that which We have sent down (i.e. the Qur'an) to Our slave (Muhammad صلى الله عليه وسلم), then produce a Surah (chapter) of the like thereof and call your witnesses (supporters and helpers) besides Allah, if you are truthful.

(4) (This is) the truth from your Lord. So be you not one of those who doubt.

(5) O you who believe! When you contract a debt for a fixed period, write it down. Let a scribe write it down in justice between you. Let not the scribe refuse to write as Allah has taught him, so let him write. Let him (the debtor) who incurs the liability dictate, and he must fear Allah, his Lord, and diminish not anything of what he owes. But if the debtor is of poor understanding, or weak, or is unable to dictate for himself, then let his guardian dictate in justice. And get two witnesses out of your own men. And if there are not two men (available), then a man and two women, such as you agree for witnesses, so that if one of them (two women) errs, the other can remind her. And the witnesses should not refuse when they are called (for evidence). You should not become weary to write it (your contract), whether it be small or big, for its fixed term, that is more just with Allah; more solid as evidence, and more convenient to prevent doubts among yourselves, save when it is a present trade which you carry out on the spot among yourselves, then there is no sin on you if you do not write it down. But take witnesses whenever you make a commercial contract. Let neither scribe nor witness suffer any harm, but if you do (such harm), it would be wickedness in you. So be afraid of Allah; and Allah teaches you. And Allah is the All-Knower of each and everything.

(6) "Our Lord! Verily, it is You Who will gather mankind together on the Day about which there is no doubt. Verily, Allah never breaks His Promise".

(7) How (will it be) when We gather them together on the Day about which there is no doubt (i.e. the Day of Resurrection). And each person will be paid in full what he has earned? And they will not be dealt with unjustly.

(8) (This is) the truth from your Lord, so be not of those who doubt.

(9) Allah! La ilaha illa Huwa (none has the right to be worshipped but He). Surely, He will gather you together on the Day of Resurrection about which there is no doubt. And who is truer in statement than Allah?

(10) And because of their saying (in boast), "We killed Messiah 'Îsa (Jesus), son of Maryam (Mary), the Messenger of Allah," - but they killed him not, nor crucified him, but it appeared so to them [the resemblance of 'Îsa (Jesus) was put over another man (and they killed that man)], and those who differ therein are full of doubts. They have no (certain) knowledge, they follow nothing but conjecture. For surely; they killed him not [i.e. 'Îsa (Jesus), son of Maryam (Mary) عليهما السلام]: