The word(s) "brethren" appears 17 time(s) in 16 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) On this world and the hereafter. And they ask you concerning the orphans Say: To set right for them (their affairs) is good, and if you become co-partners with them, they are your brethren; and Allah knows the mischief-maker and the pacemaker, and if Allah had pleased, He would certainly have caused you to fall into a difficulty; surely Allah is Mighty, Wise.

(2) And hold fast by the covenant of Allah all together and be not disunited, and remember the favor of Allah on you when you were enemies, then He united your hearts so by His favor you became brethren; and you were on the brink of a pit of fire, then He saved you from it, thus does Allah make clear to you His communications that you may follow the right way.

(3) O you who believe! be not like those who disbelieve and say of their brethren when they travel in the earth or engage in fighting: Had they been with us, they would not have died and they would not have been slain; so Allah makes this to be an intense regret in their hearts; and Allah gives life and causes death and Allah sees what you do.

(4) Those who said of their brethren whilst they (themselves) held back: Had they obeyed us, they would not have been killed. Say: Then avert death from yourselves if you speak the truth.

(5) They ask you for a decision of the law. Say: Allah gives you a decision concerning the person who has neither parents nor offspring; if a man dies (and) he has no son and he has a sister, she shall have half of what he leaves, and he shall be her heir she has no son; but if there be two (sisters), they shall have two-thirds of what he leaves; and if there are brethren, men and women, then the male shall have the like of the portion of two females; Allah makes clear to you, lest you err; and Allah knows all things.

(6) And from among their fathers and their descendants and their brethren, and We chose them and guided them into the right way.

(7) And their brethren increase them in error, then they cease not.

(8) But if they repent and keep up prayer and pay the poor-rate, they are your brethren in faith; and We make the communications clear for a people who know.

(9) Say: If your fathers and your sons and your brethren and your mates and your kinsfolk and property which you have acquired, and the slackness of trade which you fear and dwellings which you like, are dearer to you than Allah and His Apostle and striving in His way, then wait till Allah brings about His command: and Allah does not guide the transgressing people.

(10) And We will root out whatever of rancor is in their breasts-- (they shall be) as brethren, on raised couches, face to face.