The word(s) "sinful" appears 10 time(s) in 10 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) And if you are upon a journey and you do not find a scribe, then (there may be) a security taken into possession; but if one of you trusts another, then he who is trusted should deliver his trust, and let him be careful (of his duty to) Allah, his Lord; and do not conceal testimony, and whoever conceals it, his heart is surely sinful; and Allah knows what you do.

(2) And do not plead on behalf of those who act unfaithfully to their souls; surely Allah does not love him who is treacherous, sinful;

(3) Why do not the learned men and the doctors of law prohibit them from their speaking of what is sinful and their eating of what is unlawfully acquired? Certainly evil is that which they work.

(4) They descend upon every lying, sinful one,

(5) Is the food of the sinful

(6) Woe to every sinful liar,

(7) They shall not hear therein vain or sinful discourse,

(8) Forbidder of good, outstepping the limits, sinful,

(9) And none gives the lie to it but every exceeder of limits, sinful one

(10) A lying, sinful forehead.