The word(s) "fast" appears 42 time(s) in 39 verse(s) in Quran in Abdullah Yusuf Ali translation.

(21) O ye who believe! Kill not game while in the sacred precincts or in pilgrim garb. If any of you doth so intentionally, the compensation is an offering, brought to the Ka'ba, of a domestic animal equivalent to the one he killed, as adjudged by two just men among you; or by way of atonement, the feeding of the indigent; or its equivalent in fasts: that he may taste of the penalty of his deed. Allah forgives what is past: for repetition Allah will exact from him the penalty. For Allah is Exalted, and Lord of Retribution.

(22) And We ordained laws for him in the tablets in all matters, both commanding and explaining all things, (and said): "Take and hold these with firmness, and enjoin thy people to hold fast by the best in the precepts: soon shall I show you the homes of the wicked,- (How they lie desolate)."

(23) As to those who hold fast by the Book and establish regular prayer,- never shall We suffer the reward of the righteous to perish.

(24) And be steadfast in patience; for verily Allah will not suffer the reward of the righteous to perish.

(25) But she in whose house he was, sought to seduce him from his (true) self: she fastened the doors, and said: "Now come, thou (dear one)!" He said: "Allah forbid! truly (thy husband) is my lord! he made my sojourn agreeable! truly to no good come those who do wrong!"

(26) Every man's fate We have fastened on his own neck: On the Day of Judgment We shall bring out for him a scroll, which he will see spread open.

(27) "So eat and drink and cool (thine) eye. And if thou dost see any man, say, 'I have vowed a fast to (Allah) Most Gracious, and this day will I enter into not talk with any human being'"

(28) And strive in His cause as ye ought to strive, (with sincerity and under discipline). He has chosen you, and has imposed no difficulties on you in religion; it is the cult of your father Abraham. It is He Who has named you Muslims, both before and in this (Revelation); that the Messenger may be a witness for you, and ye be witnesses for mankind! So establish regular Prayer, give regular Charity, and hold fast to Allah! He is your Protector - the Best to protect and the Best to help!

(29) But those who had been granted (true) knowledge said: "Alas for you! The reward of Allah (in the Hereafter) is best for those who believe and work righteousness: but this none shall attain, save those who steadfastly persevere (in good)."

(30) For Muslim men and women,- for believing men and women, for devout men and women, for true men and women, for men and women who are patient and constant, for men and women who humble themselves, for men and women who give in Charity, for men and women who fast (and deny themselves), for men and women who guard their chastity, and for men and women who engage much in Allah's praise,- for them has Allah prepared forgiveness and great reward.