The word(s) "believer" appears 309 time(s) in 259 verse(s) in Quran in Abdullah Yusuf Ali translation.

(111) (He hath made it) Straight (and Clear) in order that He may warn (the godless) of a terrible Punishment from Him, and that He may give Glad Tidings to the believers who work righteous deeds, that they shall have a goodly Reward,

(112) We only send the messengers to give Glad Tidings and to give warnings: But the unbelievers dispute with vain argument, in order therewith to weaken the truth, and they treat My Signs as a jest, as also the fact that they are warned!

(113) And We shall present Hell that day for Unbelievers to see, all spread out,-

(114) (Unbelievers) whose eyes had been under a veil from remembrance of Me, and who had been unable even to hear.

(115) Do the Unbelievers think that they can take My servants as protectors besides Me? Verily We have prepared Hell for the Unbelievers for (their) entertainment.

(116) But the sects differ among themselves: and woe to the unbelievers because of the (coming) Judgment of a Momentous Day!

(117) When Our Clear Signs are rehearsed to them, the Unbelievers say to those who believe, "Which of the two sides is best in point of position? Which makes the best show in council?"

(118) Seest thou not that We have set the Evil Ones on against the unbelievers, to incite them with fury?

(119) But such as come to Him as believers who have worked righteous deeds,- for them are ranks exalted,-

(120) Do not the Unbelievers see that the heavens and the earth were joined together (as one unit of creation), before we clove them asunder? We made from water every living thing. Will they not then believe?