The word(s) "let" appears 241 time(s) in 215 verse(s) in Quran in Mohsin Khan translation.

(171) And those who disbelieve (the strong and wealthy) say of those who believe (the weak and poor): "Had it (Islamic Monotheism to which Muhammad صلى الله عليه وسلم is inviting mankind) been a good thing, they (the weak and poor) would not have preceded us thereto!" And when they have not let themselves be guided by it (this Qur'an), they say: "This is an ancient lie!"

(172) And indeed We had firmly established them with that wherewith We have not established you (O Quraish)! And We had assigned them the (faculties of) hearing (ears), seeing (eyes), and hearts; but their hearing (ears), seeing (eyes), and their hearts availed them nothing since they used to deny the Ayat (Allah's Prophets and their Prophethood, proofs, evidence, verses, signs, revelations) of Allah, and they were completely encircled by that which they used to mock at!

(173) Then why did those whom they had taken for alihah (gods) besides Allah, as a way of approach (to Allah) not help them? Nay, but they vanished completely from them (when there came the torment). And that was their lie, and their inventions which they had been inventing (before their destruction).

(174) So, when you meet (in fight - Jihad in Allah's Cause) those who disbelieve, smite (their) necks till when you have killed and wounded many of them, then bind a bond firmly (on them, i.e. take them as captives). Thereafter (is the time) either for generosity (i.e. free them without ransom), or ransom (according to what benefits Islam), until the war lays down its burden. Thus [you are ordered by Allah to continue in carrying out Jihad against the disbelievers till they embrace Islam and are saved from the punishment in the Hell-fire or at least come under your protection], but if it had been Allah's Will, He Himself could certainly have punished them (without you). But (He lets you fight) in order to test some of you with others. But those who are killed in the Way of Allah, He will never let their deeds be lost.

(175) Have they not travelled through the earth, and seen what was the end of those before them? Allah destroyed them completely, and a similar (fate awaits) the disbelievers.

(176) That Allah may forgive you your sins of the past and the future, and complete His Favour on you, and guide you on the Straight Path,

(177) O you who believe! let not a group scoff at another group, it may be that the latter are better than the former. Nor let (some) women scoff at other women, it may be that the latter are better than the former. Nor defame one another, nor insult one another by nicknames. How bad is it to insult one's brother after having Faith [i.e. to call your Muslim brother (a faithful believer) as: "O sinner", or "O wicked"]. And whosoever does not repent, then such are indeed Zalimun (wrong-doers, etc.).

(178) Qaf. [These letters (Qaf, etc.) are one of the miracles of the Qur'an, and none but Allah (Alone) knows their meanings]. By the Glorious Qur'an.

(179) And verily, for those who do wrong, there is a portion of torment like to the evil portion of torment (which came for) their likes (of old); so let them not ask Me to hasten on!

(180) let them then produce a recital like unto it (the Qur'an) if they are truthful.