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

(41) If We had sent unto thee a written (message) on parchment, so that they could touch it with their hands, the Unbelievers would have been sure to say: "This is nothing but obvious magic!"

(42) Of them there are some who (pretend to) listen to thee; but We have thrown veils on their hearts, So they understand it not, and deafness in their ears; if they saw every one of the signs, not they will believe in them; in so much that when they come to thee, they (but) dispute with thee; the Unbelievers say: "These are nothing but tales of the ancients."

(43) A Book revealed unto thee,- So let thy heart be oppressed no more by any difficulty on that account,- that with it thou mightest warn (the erring) and teach the believers).

(44) The leaders of the Unbelievers among his people said: "Ah! we see thou art an imbecile!" and "We think thou art a liar!"

(45) The leaders, the unbelievers among his people, said: "If ye follow Shu'aib, be sure then ye are ruined!"

(46) For, believers are those who, when Allah is mentioned, feel a tremor in their hearts, and when they hear His signs rehearsed, find their faith strengthened, and put (all) their trust in their Lord;

(47) Such in truth are the believers: they have grades of dignity with their Lord, and forgiveness, and generous sustenance:

(48) Just as thy Lord ordered thee out of thy house in truth, even though a party among the believers disliked it,

(49) Behold! Allah promised you one of the two (enemy) parties, that it should be yours: Ye wished that the one unarmed should be yours, but Allah willed to justify the Truth according to His words and to cut off the roots of the Unbelievers;-

(50) Remember thy Lord inspired the angels (with the message): "I am with you: give firmness to the believers: I will instil terror into the hearts of the Unbelievers: smite ye above their necks and smite all their finger-tips off them."