The word(s) "purity" appears 2 time(s) in 2 verse(s) in Quran in Mohsin Khan translation.

(1) O you who believe! Approach not As-Salat (the prayer) when you are in a drunken state until you know (the meaning) of what you utter, nor when you are in a state of Janaba ,(i.e. in a state of sexual impurity and have not yet taken a bath) except when travelling on the road (without enough water, or just passing through a mosque), till you wash your whole body. And if you are ill, or on a journey, or one of you comes after answering the call of nature, or you have been in contact with women (by sexual relations) and you find no water, perform Tayammum with clean earth and rub therewith your faces and hands (Tayammum) . Truly, Allah is Ever Oft-Pardoning, Oft-Forgiving.

(2) Those who avoid great sins (See the Qur'an, Verses: 6:152,153) and Al-Fawahish (illegal sexual intercourse) except the small faults, - verily, your Lord is of Vast Forgiveness. He knows you well when He created you from the earth (Adam), and when you were fetuses in your mothers' wombs. So ascribe not purity to yourselves. He knows best him who fears Allah and keeps his duty to Him [i.e. those who are Al-Muttaqun (the pious. See V.2:2)].