The word(s) "firm" appears 109 time(s) in 108 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) It is He Who hath created for you all things that are on earth; Moreover His design comprehended the heavens, for He gave order and perfection to the seven firmaments; and of all things He hath perfect knowledge.

(2) And believe in what I reveal, confirming the revelation which is with you, and be not the first to reject Faith therein, nor sell My Signs for a small price; and fear Me, and Me alone.

(3) And remember We took your covenant and We raised above you (The towering height) of Mount (Sinai): (Saying): "Hold firmly to what We have given you and bring (ever) to remembrance what is therein: Perchance ye may fear Allah."

(4) And when there comes to them a Book from Allah, confirming what is with them,- although from of old they had prayed for victory against those without Faith,- when there comes to them that which they (should) have recognised, they refuse to believe in it but the curse of Allah is on those without Faith.

(5) When it is said to them, "Believe in what Allah Hath sent down, "they say, "We believe in what was sent down to us:" yet they reject all besides, even if it be Truth confirming what is with them. Say: "Why then have ye slain the prophets of Allah in times gone by, if ye did indeed believe?"

(6) And remember We took your covenant and We raised above you (the towering height) of Mount (Sinai): (Saying): "Hold firmly to what We have given you, and hearken (to the Law)": They said:" We hear, and we disobey:" And they had to drink into their hearts (of the taint) of the calf because of their Faithlessness. Say: "Vile indeed are the behests of your Faith if ye have any faith!"

(7) Say: Whoever is an enemy to Gabriel-for he brings down the (revelation) to thy heart by Allah's will, a confirmation of what went before, and guidance and glad tidings for those who believe,-

(8) And when there came to them a messenger from Allah, confirming what was with them, a party of the people of the Book threw away the Book of Allah behind their backs, as if (it had been something) they did not know!

(9) Say those without knowledge: "Why speaketh not Allah unto us? or why cometh not unto us a Sign?" So said the people before them words of similar import. Their hearts are alike. We have indeed made clear the Signs unto any people who hold firmly to Faith (in their hearts).

(10) It is not righteousness that ye turn your faces Towards east or West; but it is righteousness- to believe in Allah and the Last Day, and the Angels, and the Book, and the Messengers; to spend of your substance, out of love for Him, for your kin, for orphans, for the needy, for the wayfarer, for those who ask, and for the ransom of slaves; to be steadfast in prayer, and practice regular charity; to fulfil the contracts which ye have made; and to be firm and patient, in pain (or suffering) and adversity, and throughout all periods of panic. Such are the people of truth, the Allah-fearing.