The word(s) "doubt" appears 60 time(s) in 58 verse(s) in Quran in Muhammad Pickthal translation.

(1) This is the Scripture whereof there is no doubt, a guidance unto those who ward off (evil).

(2) And if ye are in doubt concerning that which We reveal unto Our slave (Muhammad), then produce a surah of the like thereof, and call your witness beside Allah if ye are truthful.

(3) O ye who believe! When ye contract a debt for a fixed term, record it in writing. Let a scribe record it in writing between you in (terms of) equity. No scribe should refuse to write as Allah hath taught him, so let him write, and let him who incurreth the debt dictate, and let him observe his duty to Allah his Lord, and diminish naught thereof. But if he who oweth the debt is of low understanding, or weak, or unable himself to dictate, then let the guardian of his interests dictate in (terms of) equity. And call to witness, from among your men, two witnesses. And if two men be not (at hand) then a man and two women, of such as ye approve as witnesses, so that if the one erreth (through forgetfulness) the other will remember. And the witnesses must not refuse when they are summoned. Be not averse to writing down (the contract) whether it be small or great, with (record of) the term thereof. That is more equitable in the sight of Allah and more sure for testimony, and the best way of avoiding doubt between you; save only in the case when it is actual merchandise which ye transfer among yourselves from hand to hand. In that case it is no sin for you if ye write it not. And have witnesses when ye sell one to another, and let no harm be done to scribe or witness. If ye do (harm to them) lo! it is a sin in you. Observe your duty to Allah. Allah is teaching you. And Allah is knower of all things.

(4) He it is Who hath revealed unto thee (Muhammad) the Scripture wherein are clear revelations - they are the substance of the Book - and others (which are) allegorical. But those in whose hearts is doubt pursue, forsooth, that which is allegorical seeking (to cause) dissension by seeking to explain it. None knoweth its explanation save Allah. And those who are of sound instruction say: We believe therein; the whole is from our Lord; but only men of understanding really heed.

(5) Our Lord! Lo! it is Thou Who gatherest mankind together to a Day of which there is no doubt. Lo! Allah faileth not to keep the tryst.

(6) How (will it be with them) when We have brought them all together to a Day of which there is no doubt, when every soul will be paid in full what it hath earned, and they will not be wronged.

(7) Allah! There is no Allah save Him. He gathereth you all unto a Day of Resurrection whereof there is no doubt. Who is more true in statement than Allah?

(8) And because of their saying: We slew the Messiah, Jesus son of Mary, Allah's messenger - they slew him not nor crucified him, but it appeared so unto them; and lo! those who disagree concerning it are in doubt thereof; they have no knowledge thereof save pursuit of a conjecture; they slew him not for certain.

(9) O ye who believe! Let there be witnesses between you when death draweth nigh unto one of you, at the time of bequest - two witnesses, just men from among you, or two others from another tribe, in case ye are campaigning in the land and the calamity of death befall you. Ye shall empanel them both after the prayer, and, if ye doubt, they shall be made to swear by Allah (saying): We will not take a bribe, even though it were (on behalf of) a near kinsman nor will we hide the testimony of Allah, for then indeed we should be of the sinful.

(10) He it is Who hath created you from clay, and hath decreed a term for you. A term is fixed with Him. Yet still ye doubt!