The word(s) "disbelief" appears 37 time(s) in 35 verse(s) in Quran in Muhammad Pickthal translation.

(31) And whosoever disbelieveth, let not his disbelief afflict thee (O Muhammad). Unto Us is their return, and We shall tell them what they did. Lo! Allah is Aware of what is in the breasts (of men).

(32) He it is Who hath made you regents in the earth; so he who disbelieveth, his disbelief be on his own head. Their disbelief increaseth for the disbelievers, in their Lord's sight, naught save abhorrence. Their disbelief increaseth for the disbelievers naught save loss.

(33) And when some hurt toucheth man, he crieth unto his Lord, turning unto Him (repentant). Then, when He granteth him a boon from Him he forgetteth that for which he cried unto Him before, and setteth up rivals to Allah that he may beguile (men) from his way. Say (O Muhammad, unto such an one): Take pleasure in thy disbelief a while. Lo! thou art of the owners of the Fire.

(34) Lo! We withdraw the torment a little. Lo! ye return (to disbelief).

(35) And know that the messenger of Allah is among you. If he were to obey you in much of the government, ye would surely be in trouble; but Allah hath endeared the faith to you and hath beautified it in your hearts, and hath made disbelief and lewdness and rebellion hateful unto you. Such are they who are the rightly guided.