The word(s) "beware" appears 4 time(s) in 4 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) And there is no blame on you respecting that which you speak indirectly in the asking of (such) women in marriage or keep (the proposal) concealed within your minds; Allah knows that you will mention them, but do not give them a promise in secret unless you speak in a lawful manner, and do not confirm the marriage tie until the writing is fulfilled, and know that Allah knows what is in your minds, therefore beware of Him, and know that Allah is Forgiving, Forbearing.

(2) Do not hold the Apostle's calling (you) among you to be like your calling one to the other; Allah indeed knows those who steal away from among you, concealing themselves; therefore let those beware who go against his order lest a trial afflict them or there befall them a painful chastisement.

(3) And when you see them, their persons will please you, and If they speak, you will listen to their speech; (they are) as if they were big pieces of wood clad with garments; they think every cry to be against them. They are the enemy, therefore beware of them; may Allah destroy them, whence are they turned back?

(4) O you who believe! surely from among your wives and your children there is an enemy to you; therefore beware of them; and if you pardon and forbear and forgive, then surely Allah is Forgiving, Merciful.