The word(s) "lest" appears 73 time(s) in 69 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) "And believe no one unless he follows your religion." Say: "True guidance is the Guidance of Allah: (Fear ye) lest a revelation be sent to someone (else) Like unto that which was sent unto you? or that those (Receiving such revelation) should engage you in argument before your Lord?" Say: "All bounties are in the hand of Allah: He granteth them to whom He pleaseth: And Allah careth for all, and He knoweth all things."

(2) But no, by the Lord, they can have no (real) Faith, until they make thee judge in all disputes between them, and find in their souls no resistance against Thy decisions, but accept them with the fullest conviction.

(3) They have "Obedience" on their lips; but when they leave thee, a section of them Meditate all night on things very different from what thou tellest them. But Allah records their nightly (plots): So keep clear of them, and put thy trust in Allah, and enough is Allah as a disposer of affairs.

(4) O ye who believe! stand out firmly for justice, as witnesses to Allah, even as against yourselves, or your parents, or your kin, and whether it be (against) rich or poor: for Allah can best protect both. Follow not the lusts (of your hearts), lest ye swerve, and if ye distort (justice) or decline to do justice, verily Allah is well-acquainted with all that ye do.

(5) They ask thee for a legal decision. Say: Allah directs (thus) about those who leave no descendants or ascendants as heirs. If it is a man that dies, leaving a sister but no child, she shall have half the inheritance: If (such a deceased was) a woman, who left no child, Her brother takes her inheritance: If there are two sisters, they shall have two-thirds of the inheritance (between them): if there are brothers and sisters, (they share), the male having twice the share of the female. Thus doth Allah make clear to you (His law), lest ye err. And Allah hath knowledge of all things.

(6) O People of the Book! Now hath come unto you, making (things) clear unto you, Our Messenger, after the break in (the series of) our messengers, lest ye should say: "There came unto us no bringer of glad tidings and no warner (from evil)": But now hath come unto you a bringer of glad tidings and a warner (from evil). And Allah hath power over all things.

(7) And this (He commands): Judge thou between them by what Allah hath revealed, and follow not their vain desires, but beware of them lest they beguile thee from any of that (teaching) which Allah hath sent down to thee. And if they turn away, be assured that for some of their crime it is Allah's purpose to punish them. And truly most men are rebellious.

(8) Those in whose hearts is a disease - thou seest how eagerly they run about amongst them, saying: "We do fear lest a change of fortune bring us disaster." Ah! perhaps Allah will give (thee) victory, or a decision according to His will. Then will they repent of the thoughts which they secretly harboured in their hearts.

(9) Then will Allah say: "O Jesus the son of Mary! Recount My favour to thee and to thy mother. Behold! I strengthened thee with the holy spirit, so that thou didst speak to the people in childhood and in maturity. Behold! I taught thee the Book and Wisdom, the Law and the Gospel and behold! thou makest out of clay, as it were, the figure of a bird, by My leave, and thou breathest into it and it becometh a bird by My leave, and thou healest those born blind, and the lepers, by My leave. And behold! thou bringest forth the dead by My leave. And behold! I did restrain the Children of Israel from (violence to) thee when thou didst show them the clear Signs, and the unbelievers among them said: 'This is nothing but evident magic.'

(10) Revile not ye those whom they call upon besides Allah, lest they out of spite revile Allah in their ignorance. Thus have We made alluring to each people its own doings. In the end will they return to their Lord, and We shall then tell them the truth of all that they did.