The word(s) "faithful" appears 37 time(s) in 30 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) O children of Israel! call to mind My favor which I bestowed on you and be faithful to (your) covenant with Me, I will fulfill (My) covenant with you; and of Me, Me alone, should you be afraid.

(2) It is made lawful to you to go into your wives on the night of the fast; they are an apparel for you and you are an apparel for them; Allah knew that you acted unfaithfully to yourselves, so He has turned to you (mercifully) and removed from you (this burden); so now be in contact with them and seek what Allah has ordained for you, and eat and drink until the whiteness of the day becomes distinct from the blackness of the night at dawn, then complete the fast till night, and have not contact with them while you keep to the mosques; these are the limits of Allah, so do not go near them. Thus does Allah make clear His communications for men that they may guard (against evil).

(3) And it is not attributable to a prophet that he should act unfaithfully; and he who acts unfaithfully shall bring that in respect of which he has acted unfaithfully on the day of resurrection; then shall every soul be paid back fully what it has earned, and they shall not be dealt with unjustly.

(4) And do not plead on behalf of those who act unfaithfully to their souls; surely Allah does not love him who is treacherous, sinful;

(5) I deliver to you the messages of my Lord and I am a faithful adviser to you:

(6) And We did not find in most of them any (faithfulness to) covenant, and We found most of them to be certainly transgressors.

(7) O you who believe! be not unfaithful to Allah and the Apostle, nor be unfaithful to your trusts while you know.

(8) And if they intend to act unfaithfully towards you, so indeed they acted unfaithfully towards Allah before, but He gave (you) mastery over them; and Allah is Knowing, Wise.

(9) And there are some of them who molest the Prophet and say: He is one who believes every thing that he hears; say: A hearer of good for you (who) believes in Allah and believes the faithful and a mercy for those of you who believe; and (as for) those who molest the Apostle of Allah, they shall have a painful punishment.

(10) They who taunt those of the faithful who give their alms freely, and those who give to the extent of their earnings and scoff at them; Allah will pay them back their scoffing, and they shall have a painful chastisement.