The word(s) "believing" appears 53 time(s) in 43 verse(s) in Quran in Mohsin Khan translation.

(1) And do not marry Al-Mushrikat (idolatresses, etc.) till they believe (worship Allah Alone). And indeed a slave woman who believes is better than a (free) Mushrikah (idolatress), even though she pleases you. And give not (your daughters) in marriage to Al-Mushrikun till they believe (in Allah Alone) and verily, a believing slave is better than a (free) Mushrik (idolater), even though he pleases you. Those (Al-Mushrikun) invite you to the Fire, but Allah invites (you) to Paradise and Forgiveness by His Leave, and makes His Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) clear to mankind that they may remember.

(2) And when they advanced to meet Jalut (Goliath) and his forces, they invoked: "Our Lord! Pour forth on us patience, and set firm our feet and make us victorious over the disbelieving people."

(3) O you who believe! Do not render in vain your Sadaqah (charity) by reminders of your generosity or by injury, like him who spends his wealth to be seen of men, and he does not believe in Allah, nor in the Last Day. His likeness is the likeness of a smooth rock on which is a little dust; on it falls heavy rain which leaves it bare. They are not able to do anything with what they have earned. And Allah does not guide the disbelieving people.

(4) Allah burdens not a person beyond his scope. He gets reward for that (good) which he has earned, and he is punished for that (evil) which he has earned. "Our Lord! Punish us not if we forget or fall into error, our Lord! Lay not on us a burden like that which You did lay on those before us (Jews and Christians); our Lord! Put not on us a burden greater than we have strength to bear. Pardon us and grant us Forgiveness. Have mercy on us. You are our Maula (Patron, Supporter and Protector, etc.) and give us victory over the disbelieving people. "

(5) Then the angels called him, while he was standing in prayer in Al-Mihrab (a praying place or a private room), (saying): "Allah gives you glad tidings of Yahya (John), confirming (believing in) the word from Allah [i.e. the creation of 'Îsa (Jesus) عليه السلام, the Word from Allah ("Be!" - and he was!)], noble, keeping away from sexual relations with women, a Prophet, from among the righteous."

(6) And they said nothing but: "Our Lord! Forgive us our sins and our transgressions (in keeping our duties to You), establish our feet firmly, and give us victory over the disbelieving folk."

(7) And whoever of you have not the means wherewith to wed free, believing women, they may wed believing girls from among those (slaves) whom your right hands possess, and Allah has full knowledge about your Faith; you are one from another. Wed them with the permission of their own folk (guardians, Auliya' or masters) and give them their Mahr according to what is reasonable; they (the above said captive and slave-girls) should be chaste, not committing illegal sex, nor taking boy-friends. And after they have been taken in wedlock, if they commit illegal sexual intercourse, their punishment is half that for free (unmarried) women. This is for him among you who is afraid of being harmed in his religion or in his body; but it is better for you that you practise self-restraint, and Allah is Oft-Forgiving, Most Merciful.

(8) It is not for a believer to kill a believer except (that it be) by mistake; and whosoever kills a believer by mistake, (it is ordained that) he must set free a believing slave and a compensation (blood-money, i.e. Diya) be given to the deceased's family unless they remit it. If the deceased belonged to a people at war with you and he was a believer, the freeing of a believing slave (is prescribed); and if he belonged to a people with whom you have a treaty of mutual alliance, compensation (blood-money - Diya) must be paid to his family, and a believing slave must be freed. And whoso finds this (the penance of freeing a slave) beyond his means, he must fast for two consecutive months in order to seek repentance from Allah. And Allah is Ever All-Knowing, All-Wise.

(9) Verily, those who disbelieve in Allah and His Messengers and wish to make distinction between Allah and His Messengers (by believing in Allah and disbelieving in His Messengers) saying, "We believe in some but reject others," and wish to adopt a way in between.

(10) Say (O Muhammad صلى الله عليه وسلم): "O people of the Scripture (Jews and Christians)! Exceed not the limits in your religion (by believing in something) other than the truth, and do not follow the vain desires of people who went astray before and who misled many, and strayed (themselves) from the Right Path."