The word(s) "gain" appears 351 time(s) in 314 verse(s) in Quran in Mohsin Khan translation.

(21) Let not the believers take the disbelievers as Auliya (supporters, helpers) instead of the believers, and whoever does that will never be helped by Allah in any way, except if you indeed fear a danger from them. And Allah warns you against Himself (His punishment) , and to Allah is the final return.

(22) On the Day when every person will be confronted with all the good he has done, and all the evil he has done, he will wish that there were a great distance between him and his evil. And Allah warns you against Himself (His punishment) and Allah is full of kindness to (His) slaves.

(23) He said: "O my Lord! Make a sign for me." Allah said: "Your sign is that you shall not speak to mankind for three days except with signals. And remember your Lord much (by praising Him again and again), and glorify (Him) in the afternoon and in the morning. "

(24) Among the people of the Scripture (Jews and Christians) is he who, if entrusted with a Qintar (a great amount of wealth, etc.), will readily pay it back; and among them there is he who, if entrusted with a single silver coin, will not repay it unless you constantly stand demanding, because they say: "There is no blame on us to betray and take the properties of the illiterates (Arabs)." But they tell a lie against Allah while they know it.

(25) Verily, those who purchase a small gain at the cost of Allah's Covenant and their oaths, they shall have no portion in the Hereafter (Paradise). Neither will Allah speak to them, nor look at them on the Day of Resurrection, nor will He purify them, and they shall have a painful torment.

(26) And verily, among them is a party who distort the Book with their tongues (as they read), so that you may think it is from the Book, but it is not from the Book, and they say: "This is from Allah," but it is not from Allah; and they speak a lie against Allah while they know it.

(27) Then after that, whosoever shall invent a lie against Allah, ... such shall indeed be the Zalimun (disbelievers).

(28) You [true believers in Islamic Monotheism, and real followers of Prophet Muhammad صلى الله عليه وسلم) and his Sunnah] are the best of peoples ever raised up for mankind; you enjoin Al-Ma'ruf (i.e. Islamic Monotheism and all that Islam has ordained) and forbid Al-Munkar (polytheism, disbelief and all that Islam has forbidden), and you believe in Allah . And had the people of the Scripture (Jews and Christians) believed, it would have been better for them; among them are some who have faith, but most of them are Al-Fasiqun (disobedient to Allah - and rebellious against Allah's Command).

(29) They will do you no harm, barring a trifling annoyance; and if they fight against you, they will show you their backs, and they will not be helped.

(30) Surely, those who reject Faith (disbelieve in Allah and in Muhammad صلى الله عليه وسلم) as being Allah's Messenger and in all that which he صلى الله عليه وسلم has brought from Allah), neither their properties, nor their offspring will avail them aught against Allah. They are the dwellers of the Fire, therein they will abide. (Tafsir At-Tabari).