The word(s) "believing" appears 60 time(s) in 45 verse(s) in Quran in Muhammad Pickthal translation.

(31) Lo! he is one of Our believing slaves.

(32) Lo! he is one of Our believing slaves.

(33) Lo! they are two of Our believing slaves.

(34) Lo! he is one of our believing slaves.

(35) (It is said unto them): This is (your plight) because, when Allah only was invoked, ye disbelieved, but when some partner was ascribed to Him ye were believing. But the command belongeth only to Allah, the Sublime, the Majestic.

(36) And a believing man of Pharaoh's family, who hid his faith, said: Would ye kill a man because he saith: My Lord is Allah, and hath brought you clear proofs from your Lord? If he is lying, then his lie is upon him; and if he is truthful, then some of that wherewith he threateneth you will strike you. Lo! Allah guideth not one who is a prodigal, a liar.

(37) So know (O Muhammad) that there is no Allah save Allah, and ask forgiveness for thy sin and for believing men and believing women. Allah knoweth (both) your place of turmoil and your place of rest.

(38) That He may bring the believing men and the believing women into Gardens underneath which rivers flow, wherein they will abide, and may remit from them their evil deeds - That, in the sight of Allah, is the supreme triumph -

(39) These it was who disbelieved and debarred you from the Inviolable Place of Worship, and debarred the offering from reaching its goal. And if it had not been for believing men and believing women, whom ye know not - lest ye should tread them under foot and thus incur guilt for them unknowingly; that Allah might bring into His mercy whom He will - If (the believers and the disbelievers) had been clearly separated We verily had punished those of them who disbelieved with painful punishment.

(40) O ye who believe! When believing women come unto you as fugitives, examine them. Allah is Best Aware of their faith. Then, if ye know them for true believers, send them not back unto the disbelievers. They are not lawful for them (the disbelievers), nor are they (the disbelievers) lawful for them. And give them (the disbelievers) that which they have spent (upon them). And it is no sin for you to marry such women when ye have given them their dues. And hold not to the ties of disbelieving women; and ask for (the return of) that which ye have spent; and let them (the disbelievers) ask for that which they have spent. That is the judgment of Allah. He judgeth between you. Allah is Knower, Wise.